Just had a look at the logs. Your post did not get picked up at the time
Appears to have been a deadlock which resulted in build up of requests eventually leading to 503 responses being returned (Service Unavailable) by the server
Jan 22, 2019 20:49:00.593 [0716] DEBUG - Completed: [::ffff:86.40.69.222:46772] 503 GET /library/parts/5712/1547007568/file.mp4?autoAdjustQuality=0&hasMDE=1&location=wan&mediaBufferSize=74944 (444 live) 2ms 290 bytes (range: bytes=0-)
If this is still happening on current public or beta release, please let me have fresh logs from those releases - the public being currently 1.15.4.993 and beta being 1.15.5.994 and i will look into it.
If deadlocks still arising then we would need to have some specific diagnostics collected which I will advise on once it is confirmed that this is still the case
