Hi , i got the same problem with my Ainol Novo7 Aurora ver 3.
After using Custom ROM Mobiz versi 2 ( it's based Feiyu 0515 ), and 2 day ago, i lost multimedia cabapilty.
Like playing music , i dont have sound in my headphone or the speaker, but when screen in sleep mode, i got the sound.
And when Playing Video with MX Player, if i choose Hardware mode, i got blank screen and no sound, but if i choose Software mode, i can see the movie, but not the sound.
If i connect to my tv using hdmi, i can see thr movie and have sound too in my tv.
I try to change the rom with CM9 0618 , its based ICS 4.0.4, but it's not solved my problem.
And now i got new problem, when i connect to my tv, i only got blank screen, before with Mobiz i saw my desktop in my tv.
And when i play the game, i only got blank screen in my tv too, not happening in Mobiz versi 2.
After i look at dmesg in Termina Emulator, this problem realted to "[HDMI-AUDIO] PCM trigger start..." and "[HDMI-AUDIO] PCM trigger stop..."
So, when "[HDMI-AUDIO] PCM trigger start..." , all the sound and video will send to HDMI, so we don't have sound in headphone or speaker.
But, when "[HDMI-AUDIO] PCM trigger stop..." , we can get the sound in headphone and speaker.
The "[HDMI-AUDIO] PCM trigger stop..." happening when screen go to sleep, and will get "[HDMI-AUDIO] PCM trigger start..." when screen go to normal.
When i google this problem, I found out, Look like this problem only happening in Allwinner A10 based tablet...
I hope somebody could help us in here...
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Somehow, i fix this problem.
Here what i do:
1.Open My Tablet...
2.Cleaning MicroHDMI port, espesialy behind it, there is alot of pin soldering to the Board, i clean it with Cotton Bud.
3.In the proses, i make Motor Cable broken off, so i soldering it again to the Board, it realy thin cable...
When I turned on My Tablet, those "[HDMI-AUDIO] PCM trigger start..." and "[HDMI-AUDIO] PCM trigger stop..." message is gone from debug message (dmesg).
Lookslike it because some water coming through my MiniHDMI port, then cause short circuit in HDMI Audio detection, and force The Audio to go through HDMI.
Now My Ainol Novo7 Aurora have Sound again.
ps: sory for my bad english