Since later builds of CM10.2 and CM11 the Sense 5 audio blobs have been integrated. This unfortunately decreases the quality of VoIP calls through the in-built microphone and earpiece speaker and causes myself to sound muffled to the other party and they sound muffled to me. Regular telephone calls are just fine. Using a headset means there's no muffled sounds but I keep misplacing mine.
Is there any way to revert to the old ICS blobs (I think they were ICS, not sure) without breaking CM11? This is the sole reason I'm unable to use CM10.2 and CM11 because I do a lot of Skype calling on my handset. I haven't compiled a ROM before so I'm a bit ignorant as to the specifics.
I've been using 4.2.2 based ROMs in the meantime though without any fuss.