Distortion with teh voice prompts

HEllo,

I'm havong some distortions problmes with the promt voices of Asterisk, I'm using Innomedia Video phones, MTAs and X lite softphone and in all it's hear the same distortion, I have made some changes to the codecs, to have video calls support, but only add the video codecs to the sip_custom config file, (I add these h263 and h263p). I alsa changed the language to spanish (the languague of the prompt), but I still have this problem even when I returned the original voices. I don't remenber if I made some changes in any config file that can affect me (as I remenber I changed the indications.conf to ve, to mx and to us, I don't remember what was the original option).

I'll apreciate your help

Wilson