4k HDR stuttering/speed issues despite perfect iperf tests


I have a strange issue where my 4k bluray backups stutter and drop audio when connected over bonded MOCA. Kodi’s standard “source is too slow” message occasionally appears.

When a wired ethernet connection is set up, the files play just fine.

I have done iperf3 tests between the server and the Vero4k+ using the MOCA connection and am consistently seeing speeds of >900Mb

Have tested the Vero ethernet end with my laptop and am able to copy test files to the server at ~900Mb consistently.

Any idea why this might be happening??

How are you backing up your BDs? To ISO or MKV?

Mediainfo on one of the files may help: https://discourse.osmc.tv/t/mediainfo/

Logs while the problem is happening is always helpful: How to submit a useful support request - General - OSMC

To rule out the actual file, copying the file locally to the Vero is a good test.

Another good test is to use dd to copy the file as that’s a more real-life test than iperf3. On the Vero (from a ssh session)

dd if=/path/to/questionable/file.mkv of=/dev/null status=progress

Thanks for quick response!

Files are stored as (>50GB) mkvs and work perfectly when on a wired ethernet connection so can’t see them being the problem…??

Will aim to get a log while the problem is happening. Relatively new to this so appreciate your patience!

I will also try the dd test on the vero tomorrow - will be interesting to compare to the “real-life” test I did with the windows laptop (gigabit speed copy from the server no problems…). May have to cut the file into smaller pieces though!

Do the files play on the same Vero using wired ethernet or have you tested on a different system? If they do play on the Vero using wired, then it’s a problem with your MoCA connection.

You don’t need to split the file to do the dd test. Just start running it and you will see progress every second. You can always CTRL-C to stop the test instead of waiting for the copy to complete.

Ran the dd test as above and got same transfer speeds (~125MB/s). Copied ~2.4GB in 20s. Ran a couple of other tests with no drops and good speeds. MoCA seems to work very well in this regard!

Have uploaded logs below:

NB the 4k HDR file I’ve tried playing over the MoCA is the Ex Machina mkv. Plays fine over wired… Have managed to play it over MoCA on my laptop.


PS Not sure if coincidental but ever since I moved from raspberry pi to vero I have noticed very occasional stutter and audio desync on high-bitrate 1080p files that used to work cleanly before (no change in equipment/environment). There is also an issue where the picture slideshow screensaver crashes every few days (generally overnight).

Can you enable debugging and re-upload the logs after experiencing a problem?
Also: the IP is likely an internal address, so no need to redact