Sound from only 1 speaker, MPC-HC

Hi im having some problems with the sound when im using mpc-hc, Im getting sound from all speakers when using the internal audio renderer. But when i switch to another device to get surround on my amp and i play a ac-3 or e-ac3 file i only get audio from 1 speaker, if anyone knows how to fix this i would greatly appreciate it.

Also sorry if my english is bad cause it ain't my main language

Try with option "ignore system channel mixer" disabled in internal audio renderer.