Audio [Q] S3 CM11 - Low in Call Volume

Yesterday i went from stock JB to CM11.

I notice that the in call volume is quite low. And i have it on maximum.

Actually this is not an issue introduced in CM11....i had this issue on Stock JB, but in JB, there was a button whilst in call to boost it, which i pressed everytime.

However this button is not available in the new CM.

Can anyone help?