Dobly Digital/AC3 gives screeching noise


I’d like to be able and utilize the dolby digital track in most of my avi files, however, when I set AC3 passthru to “on” all I hear is an annoying screeching noise through my speakers. My reciever doesn’t switch to Dolby Digital. Any help would be much appreciated. Thanks.

I’ve had this problem with hearing it through my actual TV speakers but no through my receiver have you converted thess files to avi? or downloaded them this way?

Thanks for the reply. Yes, I downloaded the files in the avi format.

For some reason I have only had these problems with AVI no clue as to really why try mp4 or m4v if your putting it onto apple tv,