I don't get any 'unknown error', video just freezes which requires me to stop, then press play again from menu screen, and resume from the same spot.
Will get through 20-30 mins into a movie and it comes up, then shorter increments, even as short as every 2 mins of freezing. I wrote down the times as they happened to try and isolate in the log, here is an example:
Dec 06, 2014 20:14:57 [0x10b77b000] DEBUG - Request: [::ffff:192.168.1.18:50733] GET /video/:/transcode/universal/stop?session=7ms7tp01wi3s (9 live)
Dec 06, 2014 20:14:57 [0x10b77b000] DEBUG - * session => 7ms7tp01wi3s
Dec 06, 2014 20:14:57 [0x10b77b000] DEBUG - We found auth token (xxxxxxxxxxxxxxxxxxxx), enabling token-based authentication.
Dec 06, 2014 20:14:57 [0x10b77b000] DEBUG - Came in with a super-token, authorization succeeded.
Dec 06, 2014 20:14:57 [0x10cb2d000] DEBUG - Killing job.
Dec 06, 2014 20:14:57 [0x10cb2d000] DEBUG - Signalling job ID 15828 with 9
Dec 06, 2014 20:14:57 [0x10c9a4000] DEBUG - Play progress on 1251 'A Most Wanted Man' - got played 4814308 ms by account 1!
Dec 06, 2014 20:14:57 [0x10cb2d000] DEBUG - Job was already killed, not killing again.
Dec 06, 2014 20:14:57 [0x10c9a4000] DEBUG - [Now] User is kliu82 (ID: 1)
Dec 06, 2014 20:14:57 [0x10cb2d000] DEBUG - Stopping transcode session 7ms7tp01wi3s
Dec 06, 2014 20:14:57 [0x10c9a4000] DEBUG - [Now] Device is Xbox One (XboxOne).
Dec 06, 2014 20:14:57 [0x10cb2d000] DEBUG - Cleaning directory for session 7ms7tp01wi3s (/var/folders/k2/9652zxcn0rv7lx39snj09fpc0000gn/T/plex-transcode-7ms7tp01wi3s-b67a9b2a-828f-4120-9a06-30f61b4d4fcf)
Dec 06, 2014 20:14:57 [0x10c9a4000] DEBUG - [Now] Updated play state for /library/metadata/1251.
Dec 06, 2014 20:14:57 [0x10cb2d000] DEBUG - Cleaning old transcode directories.
Dec 06, 2014 20:14:57 [0x104a8e000] WARN - Transcode runner appears to have died.
Dec 06, 2014 20:14:57 [0x10bc13000] WARN - Transcode runner appears to have died.
Dec 06, 2014 20:14:57 [0x104a8e000] DEBUG - Session was stopped.
Dec 06, 2014 20:14:57 [0x10bc13000] DEBUG - Session was stopped.
Dec 06, 2014 20:14:57 [0x10cb2d000] DEBUG - Whacked session, 0 remaining.
Dec 06, 2014 20:14:57 [0x10cb2d000] DEBUG - It took 0.000058 sec to serialize a list with 0 elements.
Dec 06, 2014 20:14:57 [0x104a0b000] WARN - Transcode runner appears to have died.
Dec 06, 2014 20:14:57 [0x10caaa000] WARN - Transcode runner appears to have died.
Dec 06, 2014 20:14:57 [0x104a0b000] DEBUG - Session was stopped.
Dec 06, 2014 20:14:57 [0x10caaa000] DEBUG - Session was stopped.
Dec 06, 2014 20:14:57 [0x10caaa000] DEBUG - Cleaning directory for session 7ms7tp01wi3s (/var/folders/k2/9652zxcn0rv7lx39snj09fpc0000gn/T/plex-transcode-7ms7tp01wi3s-44a341fc-fab1-4008-8015-6b71e4f39d1a)
Dec 06, 2014 20:14:57 [0x10caaa000] DEBUG - Cleaning directory for session 7ms7tp01wi3s (/var/folders/k2/9652zxcn0rv7lx39snj09fpc0000gn/T/plex-transcode-7ms7tp01wi3s-b67a9b2a-828f-4120-9a06-30f61b4d4fcf)
Dec 06, 2014 20:15:03 [0x10c921000] DEBUG - It took 0.013513 sec to serialize a list with 1 elements.
Dec 06, 2014 20:15:08 [0x10ca27000] DEBUG - Request: [::ffff:192.168.1.18:50734] GET /library/metadata/1251?checkFiles=1 (4 live)
Dec 06, 2014 20:15:08 [0x10ca27000] DEBUG - * checkFiles => 1