Why won't my video play?

A video that shows a black screen, a stubborn spinner, or plays with the sound gone isn't always a broken link or a bad upload. Often the file itself was saved in a way that some devices refuse and others don't - which is exactly why it can work fine on your computer and do nothing at all on your phone, or play everywhere except an iPhone. Bernard can check any video or audio file on your site and tell you, in plain English, what's actually wrong - then fix it without you having to re-film or re-upload anything.

"It works on my computer but not my phone"

This is the single most common shape of the problem, and it usually isn't a coincidence. A handful of specific, well-known faults cause it:

• The file needs to fully download before it plays. Some editing and export tools save a bit of bookkeeping - basically an index of the file - at the very end instead of the front. A desktop browser can often work around that; a phone frequently can't, and just shows nothing until the whole file has arrived. That looks exactly like a dead link.
• The colours are saved in a format iPhones refuse. A desktop plays it without complaint, which is why this one so often gets blamed on the phone rather than the file.
• The video uses a format called HEVC. It plays fine on a recent iPhone or Mac, and not at all in most Windows browsers or on older Android phones, with no picture and no error.

"The sound has gone" or plays as silence

Two separate causes, both fixable:

• The sound is recorded on one channel instead of two. Some players treat that as silence even though the file genuinely has audio in it.
• The sound is saved in an unusual format that some browsers simply won't decode, so you get picture with no sound.

What the check actually tells you

Ask Bernard to check a video or audio file and it looks at the file itself, not just whether the link opens, and comes back with a plain verdict: either it plays everywhere, or it names the exact fault or faults above, one sentence each, no jargon. It only reads the file - nothing changes until you ask for the fix.

It also always adds one thing worth knowing on its own: a bare link straight to a video or audio file will not play in any browser, on any device, because of a security setting every file on your site carries. That's normal and not a fault - the file has to be embedded in a page (or played through a course lesson) rather than opened directly, and once it is, this doesn't affect it.

What the fix does

Once a fault is found, ask Bernard to fix it and it repairs the file directly rather than asking you to re-upload anything:

• It always does the lightest repair that actually works - often just moving that end-of-file bookkeeping to the front, which takes moments and changes nothing about how the video looks or sounds. A sound problem gets a sound-only fix that leaves the picture untouched. Only a colour problem needs a proper re-encode, and that's the one case where the file is rebuilt rather than lightly adjusted.
• The repaired file goes back to the exact same web address the old one used. Every page, post or lesson already showing it is fixed the moment the repair finishes - nothing to swap, nothing to republish.
• A copy of your original is kept alongside the repaired one, so the fix can be undone if it isn't right. Treat that as a rollback for shortly after the repair rather than a permanent archive - if a video matters to you, it's always worth keeping your own master copy, the same as you would with any file on your site.
• If a file already plays everywhere, Bernard won't touch it - there's nothing to fix. And if a repair is already running on a file, it won't start a second one on top of it.

This works on video files today, the common MP4 and MOV kinds specifically. Other file types can still be checked and named, just not yet repaired this way.

What this doesn't cover yet

The check reads your file the same way a visitor's browser does, from your site's own web address. That works for video and audio placed on your pages, which is where most playback trouble shows up.

It doesn't yet reach course lesson videos or paid downloads. Those are deliberately not served from your site's address at all: each one is handed to a student or buyer through a private link that expires shortly after it's issued, so nobody can share it around. That protects your work, and it also means this check has no way to read those files today. If you point Bernard at one, it will tell you so plainly rather than pretending the file is missing - so if you get that answer, nothing is wrong with your video and there's no path for you to go and hunt for. Extending the check to reach them is on the list.

Where to start

If a video is misbehaving anywhere on your site or in a course, just describe what you're seeing - "the video on my about page won't play on my phone", "my lesson video has no sound" - and Bernard checks the actual file and tells you what's wrong before doing anything. See Upload files and video to my site for getting a video onto a page in the first place, or What can I do with my videos? for everything Bernard can do with a lesson video once it's up.