Ugoos AM6B+ Magical combinations drop image when using PM4K

Help & Support Ugoos
1

My current audio setup is my 4k TV, JBL MA710 AVR, and Ugoos AM6B+ running CoreElec 21.2 Omega-Nightly, speakers are in a 7.1 configuration. My Ugoos and TV are connected to my AVR. All cables in play are Ultra High-Speed certified. Using a Blu-ray player, I verified I can play TrueHD and DTS-MA HD codecs without issue.

I am observing that certain combinations of Audio / Video cause total video loss when using PM4K. Setting the “System resolution” seems to have some impact. If I set the resolution to 4k, I cannot play either a 1080p or a 4k VC1-TRUEHD remux (Input is dropped from TV, AVR plays an instant of audio then drops). If I set the resolution to 1080p, I can play the 1080p remux but not the 4k one. So it appears the resolution is the root cause here. However, I can play a 4k DoVI/HDR10 DTS-HD-MA 5.1 remux without issue. One interesting note, is that if I connect my Ugoos to my TV directly, I can play the video fine but lose some audio codecs, for example DTS-HD-MA codecs. So I can either choose between a video or audio problem.

kodi.log: 2025-06-29 19:51:37.362 T:3966 info <general>: ----------------------------- - Pastebin.com
dmesg: https://paste.coreelec.org/TradeCinnamon

This looks suspicious


[ 1009.362525@2]- asoc-aml-card auge_sound: S/PDIF[1] Playback enable
[ 1009.397553@0]- dim:value reg:ch[0]:fix_buf:0;ponly <0,0>
[ 1009.397564@0]- dim:3840x2160-0x501000.
[ 1009.406897@0]h detect vout mode change!!!!!!!!!!!!
[ 1009.406933@0]h [tsync_avevent_locked 1064]VIDEO_START-tsync_mode:0(S)
[ 1009.406936@0]h pcr:0x0,param:0x0,vpts:0x0,apts:0xffffffff
[ 1009.511866@3]- asoc-aml-card auge_sound: S/PDIF[1] Playback disable
[ 1009.511905@3]- iec_info: rate: 192000, codec_type:0x7, channel status L:0x9001902, R:0x9001902
[ 1009.511910@3]- hdmitx: err chn setting, must be 2, 4, 6 or 8, Rst as def
[ 1009.511911@3]- hdmitx: err chn msk, must larger than 0
[ 1009.511922@3]- aml_spdif_fifo_ctrl, bit depth:16, frddr type:1, toddr:type:1
[ 1009.512138@0]- spdif_b keep clk continuous
[ 1009.512210@3]- audio_ddr_mngr: frddrs[0] released by device ff642000.audiobus:spdif_b
[ 1009.512798@1]- vout: vmode set to null
[ 1009.513556@1]- fb: current vmode=2160p60hz420, cmd: 0x10000
[ 1009.513562@1]- vlock: event MODE_CHANGE_PRE 0
[ 1009.513603@1]- hdmitx: edid: not find mapped vic
[ 1009.513622@1]- vout: new mode null set ok
[ 1009.513623@1]- fb: current vmode=null, cmd: 0x20000
[ 1009.514148@1]- hdmitx: system: set frac_rate_policy as 1
[ 1009.514208@1]- vout: vmode set to 2160p24hz
[ 1009.514575@1]- fb: current vmode=null, cmd: 0x10000
[ 1009.514587@1]- hdmitx: hdmitx_set_current_vmode[5644]

What I tried:

Any ideas? Thanks for your time.
Some random stuff:

CoreELEC:~ # cat /sys/class/display/mode
2160p24hz
2

You need try use the system, without any plex addon. Users in avs forum reported weird issues, what’s gone when they using without plex addons.

1 Like
3

Thanks for your reply, I just attempted to play the same MKV from a flash drive and experiencing the exact same issue. So I think pm4k & pkc can be ruled out.
EDIT: I was wrong. After a few minutes of buffering, the video started playing. Hmm…
After attempting to play the same MKV from the NAS directly (SMB), seeing the “black screen stutter” issue.

CoreELEC:~ # ping 192.168.4.90
PING 192.168.4.90 (192.168.4.90): 56 data bytes
64 bytes from 192.168.4.90: seq=0 ttl=64 time=0.516 ms
64 bytes from 192.168.4.90: seq=1 ttl=64 time=0.521 ms
64 bytes from 192.168.4.90: seq=2 ttl=64 time=0.527 ms
64 bytes from 192.168.4.90: seq=3 ttl=64 time=0.517 ms
64 bytes from 192.168.4.90: seq=4 ttl=64 time=0.535 ms
64 bytes from 192.168.4.90: seq=5 ttl=64 time=0.534 ms
64 bytes from 192.168.4.90: seq=6 ttl=64 time=0.527 ms
64 bytes from 192.168.4.90: seq=7 ttl=64 time=0.579 ms
64 bytes from 192.168.4.90: seq=8 ttl=64 time=0.519 ms
64 bytes from 192.168.4.90: seq=9 ttl=64 time=0.527 ms

Let’s dig deeper with iperf

CoreELEC:~ # iperf3 -s
-----------------------------------------------------------
Server listening on 5201 (test #1)
-----------------------------------------------------------
Accepted connection from 192.168.4.90, port 48990
[  5] local 192.168.4.91 port 5201 connected to 192.168.4.90 port 48992
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec   112 MBytes   939 Mbits/sec
[  5]   1.00-2.00   sec   112 MBytes   942 Mbits/sec
[  5]   2.00-3.00   sec   112 MBytes   942 Mbits/sec
[  5]   3.00-4.00   sec   112 MBytes   941 Mbits/sec
[  5]   4.00-5.00   sec   112 MBytes   941 Mbits/sec
[  5]   5.00-6.00   sec   112 MBytes   942 Mbits/sec
[  5]   6.00-7.00   sec   112 MBytes   942 Mbits/sec
[  5]   6.00-7.00   sec   112 MBytes   942 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-7.00   sec   811 MBytes   972 Mbits/sec                  receiver
iperf3: the client has terminated

iperf mid transfer shows reasonable throughput hit

Accepted connection from 192.168.4.90, port 48994
[  5] local 192.168.4.91 port 5201 connected to 192.168.4.90 port 48996
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec   101 MBytes   844 Mbits/sec
[  5]   1.00-2.00   sec   101 MBytes   845 Mbits/sec
[  5]   2.00-3.00   sec   101 MBytes   848 Mbits/sec
[  5]   3.00-4.00   sec   100 MBytes   842 Mbits/sec
[  5]   4.00-5.00   sec   102 MBytes   860 Mbits/sec
[  5]   5.00-6.00   sec   100 MBytes   840 Mbits/sec
[  5]   6.00-7.00   sec  98.6 MBytes   827 Mbits/sec
[  5]   7.00-8.00   sec   100 MBytes   842 Mbits/sec
[  5]   8.00-9.00   sec  99.2 MBytes   833 Mbits/sec
[  5]   9.00-10.00  sec   103 MBytes   863 Mbits/sec
[  5]  10.00-10.00  sec   384 KBytes   863 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-10.00  sec  1007 MBytes   844 Mbits/sec                  receiver

Gee, let’s try mounting it and reading it from there.

CoreELEC:~ # mount -t cifs -o vers=3.0,username=plex,password=plexplex //192.168.4.90/Drive /storage/devo/1/
CoreELEC:~ # ls /storage/devo/1/
#Recycle  Movies

Same issue observed attempting to play a 1080p DTS-HD MA file :frowning:
EDIT: After lots of black-screen stuttering the video eventually played normally. However the original 4k file is still not playing. The theory I have is continuous “black-screen stutter” that never catches up.

4

Swapped over to today’s NO New Order build and observing same issue.

5

It’s the receiver. Swapped it out for a Denon and it just works. JBL MA710 loses some points. If you have a JBL MA710 receiver and experiencing signal loss, it’s probably the AVR.

6

Lesson learned; in future when trying to resolve a problem first step is to connect the box directly to TV :wink:

7

That was indeed my first step.

One interesting note, is that if I connect my Ugoos to my TV directly, I can play the video fine but lose some audio codecs