Default After 4.3 to 4.1.2 brick issues, no audio etc..

I already recovered from the soft brick from trying to flash 4.1.2 in Odin while on 4.3 bootloader but these issues keep on and on no matter what ROM I flash.
I'm on Quantum ROM 4.4 KK.
Here is a list of what's wrong:
1. No audio whatsoever.
2. Can't open any apps hardly.
3. Battery dying fast.
4. Can't flash certain ROMs.
5. DSP Manager always crashing.
6. Can't play videos.

Help. Pweeze.

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