ML No532 Amp Repair

All,

So I’ve recently had a channel go out puff of smoke pop then go into protection mode. Now I have some questions about this for those who know. First the amp would pop in the bad channel on turn on, then it would pop in both channels when I would mute my preamp. Does this seem normal for that beast of an amp? Secondly, I’ve reached out to Harman about service and they gave me 3 service centers which are Pyramid Audio, Technetron Electronic Inc & United Audio. Which service center do you guys recommend since I’m in Indiana plus best in service? Any help/suggestions appreciated!

Ben