Manatee

A video that plays on your Mac but not on a TV from a USB drive

· 7 min read

When a video plays on your Mac but not from a USB drive plugged into a TV, the cause is one of three things: the drive is formatted in a way the TV cannot read, the Mac left hidden companion files the TV trips over, or the video uses a codec or container the TV’s player does not support. Check them in that order. The first two take a minute; the third usually means converting to an H.264 MP4.

Step 1: check how the drive is formatted

TVs read drives formatted for Windows PCs and cameras, not drives formatted only for Macs. If the TV says no USB device is connected, or shows the drive as empty, the format is the first suspect.

  1. Plug the drive into your Mac and open Disk Utility (in Applications, Utilities).
  2. Select the drive in the sidebar. The line under its name at the top of the window shows the format.
  3. APFS or Mac OS Extended means the TV almost certainly cannot read it. ExFAT, or MS-DOS (FAT), which is FAT32, are the formats TVs generally understand.

Changing the format means erasing the drive, which deletes everything on it, so copy its files to your Mac first. Then, in Disk Utility, select the drive, click Erase, and choose ExFAT. If an older TV still does not see it, choose View, Show All Devices, select the device itself (the top entry above the volume), and erase it again with Master Boot Record as the scheme. Some TVs only look at drives set up that way.

FAT32 has one catch: it cannot hold a single file larger than 4 GB. If your video is bigger, the Mac refuses to copy it, and the item can’t be copied because it’s too large for the volume’s format explains your options.

Step 2: remove the hidden ._ files

When a Mac copies a file to an ExFAT or FAT32 drive, it adds a hidden companion file for each one, named with a dot and an underscore in front: ._Holiday.mp4 next to Holiday.mp4. These hold Mac-only details such as tags and labels, which those formats have no place for. The Mac hides them, but many TVs do not. You see two copies of every video, and the one you pick first says the file is not supported. Press Command-Shift-Period in a Finder window on the drive and you can see them too.

To clear them, open Terminal, type dot_clean -m followed by a space, drag the drive’s icon from the desktop into the window, and press Return:

dot_clean -m /Volumes/USBDRIVE

The companion files are removed and the videos are left alone. The Mac creates new ones whenever you copy more files across, so run it again after each copy. Then eject the drive in Finder before you unplug it, so nothing is left half-written.

Step 3: check the video itself

If the drive is readable and clean but the TV still refuses a particular file, the video is the problem. Open it in QuickTime Player and choose Window, Show Movie Inspector. The Format line tells you what is inside.

  • HEVC. iPhones record this by default. Older TVs often have no decoder for it, or play it with a black picture or no sound. H.264 vs HEVC explains which devices handle which.
  • HDR or 10-bit video. Recent iPhones record HDR. A TV that does not support it may refuse the file or show pale, washed-out colors.
  • ProRes. Built for editing rather than playback, and its data rate is often too high for a USB stick to deliver smoothly even when the TV can decode it.
  • VP9 or AV1. Common in video saved from the web. Many TVs lack decoders for them.

Then look at the extension. Some TVs list .mp4 files but ignore .mov files entirely, so a screen recording or an iPhone clip in MOV may not even appear. Finally, check the resolution and frame rate: a 4K video on a 1080p TV, or 4K at a high frame rate on an older set, can stutter or refuse to start.

Step 4: convert to the format TVs agree on

The safest file for a TV is an MP4 with H.264 video and AAC audio, at no more than the TV’s own resolution. There are two ways to get one on a Mac.

With QuickTime Player. Choose File, Export As, pick 1080p (or 720p for an older set), and choose Greater Compatibility (H.264). QuickTime saves a .mov, which some TVs still ignore, so follow up with how to convert MOV to MP4 to rewrap it as an MP4 without another re-encode. This only works for videos QuickTime can open in the first place.

With Manatee. Manatee converts to an H.264 MP4 in one step, including from formats QuickTime cannot open, such as MKV, AVI or WEBM:

  1. Open Manatee and choose Convert, or drag the videos onto its menu bar icon.
  2. Drop in the files, several at once if you like.
  3. Choose MP4 as the target.
  4. Copy the new MP4s, which appear next to the originals, onto the drive.

The originals are never modified, and everything runs on your Mac with no upload. If a file is still too big for a FAT32 drive, Manatee’s Shrink mode lets you type a size in MB, below the 4 GB limit, and finds the quality that fits. It is free for 24 hours with every feature, then $9 once. It does not format drives or clean them, so steps 1 and 2 are still done with Disk Utility and Terminal.

If the converted video looks pale or flat on the TV, the original was HDR; 10-bit, HDR and the video that looks washed out explains what is going on.

Questions

The TV sees the drive but lists no videos. Why? Many TVs only list files they believe they can play, so an unsupported format looks like an empty folder. Also check that the videos are not buried several folders deep, since some TVs only look a level or two down. A folder at the top of the drive is the safest place.

Should I use ExFAT or FAT32? ExFAT first, because it has no 4 GB limit on a single file. Use FAT32 only if the TV will not read ExFAT.

The video plays but has no sound. What now? The TV can decode the picture but not the audio track. Surround formats and some lossless audio are the usual reasons. Converting to MP4 with AAC audio fixes it in most cases; the exported video has no sound covers the other causes.