Digital Signage Troubleshooting: 12 Common Faults

Almost every signage fault we are called about is one of twelve things, and none of them are difficult. The fix is usually free, takes under ten minutes, and requires nobody to drive anywhere.

What costs money is diagnosing in the wrong order: replacing a player that had a loose HDMI lead, or booking a site visit for a display that was showing exactly what it had been scheduled to show.

So this is ordered the way a technician works: symptom, likely causes in order of probability, then fixes starting with the cheapest and most likely. Work down and stop when the screen comes back. Everything applies to easyCMS on Windows, Android and LG webOS.

1. Black or blank screen

Symptom. Nothing on the panel, or a “no signal” message.

Likely causes, most probable first: display off or on the wrong input; player lost power; HDMI lead worked loose; player app did not launch at startup; nothing scheduled and no default layout.

1. Check the display’s power and input source. After a cleaning shift, a power cut or a visit from anyone with a remote control, this is the answer more often than any other cause.
2. Check the player has power, look for its status LED, and try a different socket before assuming the device is dead.
3. Re-seat the HDMI lead at both ends, then try a different lead. Leads fail more often than players do.
4. If the player is running but the screen is blank, confirm the app actually launched, and set it to start automatically on boot. See Android player setup or the guide for your platform.
5. If the app is running and the screen is still empty, the fault is content rather than hardware: check something is scheduled for right now, and set a default layout so the display always has a fallback.

2. Content not updating after publishing

Symptom. You published a change. The screen is still showing the old version.

Likely causes: the player has not collected yet; the layout is still a draft; the schedule dates or times are wrong; it went to the wrong display group; the player is offline.

1. Wait one collect interval. Players poll the CMS and pick up changes at the next check-in, so the commonest cause of “it didn’t update” is impatience. If you need it now, the CMS can push a collect request immediately.
2. Confirm the layout is published, not still a draft. An edited layout that has not been published keeps serving its previous version, intentional, and it catches everyone out once.
3. Check the schedule: dates, times, recurrence, and the right display or display group. See scheduling content.
4. Check priority and layering. A higher-priority event or an overlay can legitimately keep new content off screen.
5. Look at the display’s last accessed time in the CMS. If it is stale, this is not a content problem, go to fault 3.
6. Request a screenshot, so you are working from what the player is genuinely showing rather than what someone told you.

3. Player shows offline in the CMS

Symptom. The display’s last-accessed time has stopped advancing, or it never checked in at all.

Likely causes: site power or network; wrong CMS address or key; the display was never authorised; captive-portal or firewall blocking; full local storage.

1. Split the problem first. Never checked in at all means configuration, CMS address, key or authorisation. Was fine and then stopped means power or network at the site.
2. Confirm the device has real internet access: open a website in its browser, or ping it from another machine on the same network.
3. Check the CMS address character by character, including https:// and no trailing space, and confirm the CMS key matches the one in your CMS settings.
4. In the Displays page, confirm the display is authorised and holds a valid licence. A registered but unauthorised display waits forever without complaining.
5. Restart the player app, then the device.

Full detail is in troubleshooting offline displays. Remember too that offline in the CMS does not mean dark on the wall, a cached player carries on playing, which we cover in digital signage without internet.

4. Video stutters or freezes

Symptom. Playback judders, tears, or freezes on one particular clip while everything else is fine.

Likely causes: the file is encoded beyond what the device can decode; too many video regions at once; storage nearly full; a network stream rather than a local file.

1. Note whether it is one clip or all clips. One clip means the file; all clips means the device.
2. Re-encode the offending file as H.264 MP4 at the display’s native resolution and a sensible bitrate. A 4K 100 Mbps master will stutter on hardware that plays a well-encoded 1080p file perfectly.
3. Reduce simultaneous video. Two or three video regions at once will defeat modest hardware, and the fix is a design change rather than a bigger box.
4. Check free storage on the player and clear the local cache if it is tight.
5. If the content is a live stream, the problem is bandwidth rather than the player. Test the connection at the site during the hours the stutter happens, and keep a local copy of anything critical, see playlists and the media library.

5. Content looks blurry or pixelated

Symptom. Text has soft edges, images look mushy, the whole layout looks slightly out of focus.

Likely causes: source files smaller than the area they fill; a layout built at the wrong resolution; the display scaling a non-native signal; sharpness or overscan settings on the panel.

1. Check the source file’s actual pixel dimensions. An 800px image stretched across a 1920px region will always look soft, and no setting will fix it.
2. Build the layout at the display’s native resolution, 1920x1080 landscape, 1080x1920 portrait. A 720p layout upscaled to a 4K panel looks exactly as bad as it sounds. See creating layouts.
3. Confirm the player is outputting the panel’s native resolution, not a fallback mode.
4. Turn off the display’s sharpness enhancement and overscan. Consumer TVs ship with picture processing that ruins fine text.
5. Set text in the layout rather than flattening it into a JPEG.

6. No audio, or audio from the wrong output

Symptom. Silent video, or sound coming out of the wrong device.

Likely causes: muted somewhere in the chain; the widget’s audio is not enabled; the file has no audio track; the wrong output is selected on the player.

1. Check the physical chain first: display volume, mute button, soundbar or amplifier input and power.
2. Check the player’s own system volume. It is a separate control from the display’s and defaults low on some devices.
3. Confirm the media item’s audio is enabled in the layout, and that the file contains an audio track, play it on a desktop to be sure.
4. On Windows players, set the correct default playback device. For sound over HDMI, the HDMI output must be the default, not the onboard analogue jack. See Windows player setup.
5. If audio works on one clip but not another, re-encode the silent one with a standard AAC track.

7. Player reboot loop or random restarts

Symptom. The device restarts by itself, repeatedly or unpredictably.

Likely causes: an underpowered or failing power supply; overheating; corrupt storage; a badly configured scheduled reboot.

1. Replace the power supply with a correctly rated one. Cheap or borrowed USB adaptors cause more random reboots than anything else, and the symptom looks exactly like a dying device.
2. Check temperature and ventilation. A player sealed behind a screen or in an unventilated enclosure overheats and restarts, especially in summer or a sunlit window.
3. Check for a scheduled reboot firing at the wrong interval, and for an automatic OS update cycle you did not intend.
4. Check storage health. Cheap SD cards and USB drives corrupt under continuous writes, so a device running for years on its original card is a candidate.
5. If it survives on the bench but reboots on site, suspect the mains circuit, one shared with fridges, ovens or motors will brown out.
6. As a last resort, reinstall the player and re-register it.

8. Screen will not rotate to portrait

Symptom. The panel is physically mounted portrait, but content plays landscape with black bars, or rotated the wrong way.

Likely causes: rotation set in only one of the two places it needs to be; the layout built landscape; auto-rotate interfering.

1. Portrait needs two things: the player’s output rotated in the device’s own display settings, and a layout built at portrait dimensions. Doing only one gives exactly this symptom.
2. Rotate the output on the device. On Windows this sits in the graphics or display settings; on Android it is a display setting with auto-rotate disabled; on LG webOS orientation is set on the display itself rather than in the CMS. See LG webOS player setup.
3. Create the layout at portrait resolution, 1080x1920, not a rotated 1920x1080. See creating layouts.
4. Re-check the media inside it. Portrait layouts full of landscape photographs still look wrong even when everything else is correct.
5. Reboot after changing rotation. Some devices only apply it cleanly at startup.

9. Display will not wake or sleep on schedule

Symptom. The screen stays on all night, or fails to come on in the morning.

Likely causes: the panel’s own on/off timer conflicting with the CMS; CEC unsupported or disabled; wrong time zone or clock on the player.

1. Pick one mechanism and disable the other. A panel’s built-in on/off timer fighting a scheduled command from the CMS produces exactly this behaviour, and the built-in timer usually wins.
2. Check the player’s clock and time zone, and the time zone set for the display in the CMS. Most “off by an hour” faults are daylight saving.
3. If you control the panel over CEC, confirm the display supports it and that CEC is enabled in its menus, often off by default, and named something unhelpful.
4. Verify the schedule: correct days, correct display group, no overlapping event.
5. Where reliability matters more than energy, leave the panel on and schedule a black layout instead. Crude, and it always works.

10. Media upload fails

Symptom. The upload stalls, times out, or is rejected.

Likely causes: the account’s storage allowance is full; the file is too large or an unsupported format; a slow or dropping connection; awkward characters in the filename.

1. Check your remaining library storage. A standard easyCMS account includes 300MB, the PRO account 1GB and Enterprise 10GB. Delete unused media and empty the library’s recycled items before assuming a bug.
2. Compress the file. A 700MB video is almost never necessary; the same clip as H.264 at 1080p is a fraction of the size and looks identical from three metres.
3. Rename the file to plain characters: letters, numbers, hyphens. No accents, slashes or emoji.
4. Confirm the format is supported, and convert anything exotic to MP4, JPG, PNG or PDF.
5. Retry on a stable connection. Large uploads over hotel or mobile Wi-Fi drop silently. Playlists and the media library covers how versions and replacements are handled.

11. Cannot log in to the CMS

Symptom. Credentials rejected, or the login page reloads without an error.

Likely causes: the wrong CMS URL; caps lock or a stale saved password; a cached session; the account is disabled or the user was removed.

1. Confirm you are on the right CMS address. Bookmarks that point at an old instance produce a login page that looks correct and will never accept your password.
2. Retype the password by hand rather than letting the browser fill it, and check caps lock.
3. Clear cookies for the site, or try a private window. A stale session is the usual cause of a login page that silently reloads. Disable script- or cookie-blocking extensions while you are there.
4. Use the password reset link, and check spam for the email.
5. If a colleague created your account, confirm with them that it is still enabled and has the right permissions. If nothing works, contact support, we can verify the account state directly.

12. Player slowing down or overheating over time

Symptom. A screen that was fine for months becomes sluggish, drops frames, or restarts under load.

Likely causes: dust and blocked ventilation; storage close to full; a very long uptime; ageing storage or power supply.

1. Clean the device. Dust in a fanless enclosure raises temperature steadily, and thermal throttling looks exactly like a failing device.
2. Improve airflow. Do not seal a player behind a wall-mounted panel with no gap, and keep it out of direct sunlight.
3. Free up storage and clear the local cache so the player re-downloads only what it needs.
4. Schedule a nightly or weekly reboot out of hours. This one measure prevents most slow-degradation faults.
5. Audit your content. An oversized video added months ago drags on every loop.
6. Replace ageing storage and the power supply before replacing the player. Those are the parts that wear out.

Catching this before it becomes a call-out is what display monitoring is for: last-seen times, remote screenshots and offline alerts tell you which screen needs attention without anyone visiting.

When to contact support, and what to send us

Contact us once you have worked through the relevant list and the screen is still wrong. There is no charge for asking: free expert support comes with every easyCMS account, and the assistant and support guides are free to everyone. If you need someone hands-on the same day, an expert hour is €25.

Send these five things in the first email and we will usually diagnose in one reply instead of four:

1. The display name exactly as it appears in the CMS, so we can find it.
2. The player platform and version: Windows, Android or LG webOS, plus the version from the player’s status window.
3. A photograph or screenshot of what is on the screen. A photo of a black panel still helps; it tells us whether there is a backlight.
4. What the status window says. It reports connection state, licence and recent errors, and usually names the fault outright.
5. What changed recently. A new layout, a network change, a firmware update, a power cut, a new router. Signage that worked for a year and broke on Tuesday broke because something changed on Tuesday.

Email info@myeasycms.com or call +48 509 937 137. More ways to reach us are on the support page.