Here Coldbird explains why sound is so hard to get working on Custom Emulation Firmware (TN-V). You can see that he has sound working in the video below, but it’s really hard to here. Hopefully Coldbird can get back to his project of porting PEOPS sound plugin to Vita on TN-V soon. You can Best of luck!!! Coldbird..
“POPS is originally a multithreaded emulator, with a separate thread for audio processing on the media engine, which emulates the PSX SPU (sound processing unit).
As we don’t have access to the Media Engine secondary CPU on Vita it was necessary to remove the audio emulation thread from the emulator, rendering the PSX SPU dead.
Some games have code to wait until audio playback has been completed, in such games you will now (on Vita) suffer from lag as it will be waiting on something that is no longer there (SPU), essentially slowing the game down to the point where a timeout occurs and the game continues to run again, waiting for the next SPU event, and again timing out, rinse & repeat from here on out.
The PSX SPU also served a secondary purpose, namely multithreaded buffer copying.
Games that rely on this functionality are at this moment unsupported on Vita + CEF, as without the SPU emulator, there is no way to trigger SPU multithreaded memcpy’s anymore.
Long story short, no its not your fault, its a Vita thing, learn to live with it or code a SPU emulator for POPS that doesn’t rely on the Media Engine to do its hard lifting.
I tried porting the PEOPS sound plugin to Vita some time ago but was forced to postpone that work in progress in favor of reallife things (my job mostly).
When I get to resume it, it will probably get shipped as a plugin for TN-V7.”