Device: Ugoos AM8 Pro
SoC: Amlogic S928X
RAM: 8 GB
Boot medium: microSD
CoreELEC versions tested:
22 Alpha 1
22 Alpha 2
22 Alpha 3
22 Beta 1
DTB: stock am8 DTB supplied with each respective release
Kodi: bundled with CoreELEC
Playback:
Native Jellyfin integration
Media stored on NFS mount (kernel-level mount)
Display:
1080p projector
SDR only
No HDR
No Dolby Vision
Problem
During hardware video playback, contiguous CMA memory gradually decreases until Kodi crashes and the system reboots.
Typical failure sequence:
Video plays normally.
Audio begins looping the last buffer.
Screen turns black.
Kodi crashes.
Device reboots (watchdog).
The problem only occurs during video playback.
System is stable indefinitely when:
idle (tested for 5 days)
playing music
browsing the UI
CMA observations
Initial:
CmaFree ≈ 1985 MB
During failing playback:
44 min: CmaFree ≈ 1141 MB
51 min: CmaFree ≈ 792 MB
58 min: CmaFree ≈ 410 MB
(examble on Sherlock Holmes 2009)
After stopping playback:
CmaFree recovers only partially (approximately 670 MB), never returning to the initial value.
Starting another video after this can causes an immediate crash if little of memory was left.
Normal system RAM does not show a comparable increase.
Debugging performed
Fresh SD card formatted before every installation
No restored userdata
Multiple CoreELEC versions tested
Different Arctic and stock estuary skins tested
Debug logging enabled
CMA monitored through:
grep -i Cma /proc/meminfo
DMA-BUF inspection:
cat /sys/kernel/debug/dma_buf/bufinfo
Result remains constant:
3 DMA-BUF objects
~87 MB total
No increasing exported DMA-BUF count was observed.
Kernel log before reboot contains only repeated:
dim:warn:irq:flag 0
No GPU fault, kernel panic, or OOM messages appear before SSH connection is lost.
Codec testing
Initially AV1 appeared stable, but further testing showed codec alone is not the determining factor.
Failing file
Alice in Wonderland
MKV
AV1 Main
1920×1080
10-bit
23.976 fps
AV1 codec string: av01.0.08M.10.0.111.01.01.01.0
Video bitrate: ~8.18 Mb/s
DTS-HD MA + DTS + AC3
2 PGS subtitle tracks
Result:
Rapid CMA depletion
Crash after approximately 20 minutes
Working file
Project Hail Mary
MKV
AV1 Main
1920×1080
10-bit
24 fps
AV1 codec string: av01.0.08M.10.0.110.01.01.01.0
Video bitrate: ~0.77 Mb/s
HE-AAC stereo
35 SRT subtitle tracks
Result:
Over 2 hours playback
No measurable CMA leak
Additional testing
Disabling subtitles does not resolve the issue.
Hard factory reset, stock skin, file played from usb flash drive, movie stripped from everything except video track - no subtitles, audio, tags, chapters etc - leak stills occurred but slower
FFmpeg software decoding reports no bitstream corruption.
Audio playback alone never reproduces the problem.
System idle for multiple days remains stable.
Additional information
Im not an IT person report above is an export from AI chat after 3 days of trouble shooting and hitting the wall time and time again - if any additional information is necessary, please word it in a way layman can understand.
Approximately 80% (if not more) of my movie library of hundreds of movies are causing problems both files ripped from BD and transcoded by me as well as privatized from internet h264, h265, av1 all cause problems - tho movies and tv series with low bit-rate are in general less problematic than high quality rips
older logs as i just wiped installation to try again with clean sheet and all logs perished but the SIGSEGV is consistent with current crashes - the Crash in FT_Done_Face / FreeType was resolved by overwriting subtitles styles