Question [Q] Kernel for Note 2

Hi Guys. I have few questions about some new kernel for my Note 2. Mainly I'm talking about the quality of sound from the speaker after installing a new custom rom. On the original ROM from Samsung all sounds are clean and at the right level (i mean ringtones etc.) After installing custom rom ringtones are a little quieter and the sound is not so good. At first I thought that it is the fault of the rom, but same is in every other rom like CM , OMNIROM and now im on the C-ROM. Can someon can help me ? If I change the kernel it can be better?
And last question which kernel can be best for C-ROM and my Note 2 ?
Cheers!