I guess I'm not sure when you say "lock up" if your saying the receiver had some technical issues. Or, possibly you just had it set to "Auto" sense the incoming signal. Most DVD's are in Dolby, so that would make sense if it was Automatically selecting Dolby.

Most receivers will let you pick different surround modes, I'm guessing you may have been just doing something wrong, or had the receiver setup in Auto mode or something, not sure.

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