NAD C375BEE protection circuit activating.


I recently purchased a NAD C375BEE amplifier from an AUDIGON member and it ran fine for two weeks. Last evening the protection circuit activated after playing for a few minutes, I checked the speaker connections included those for my REL subwoofer and all were tight and not shorting yet it activated again after a few minutes of playing. I know the basic routine for trouble shooting but would like some advice and I would also like to know if activating the protection circuit several times while troubleshooting might damage the amplifier. BTW my previous amplifier was an Anthem Integrated 2 and there were no issues.
NAD C375BEE
Totem Model One Signatures
Ultech UCD-100
Birdland Odeon Lite DAC
VansEvers Clean Line Power Conditioner
Kimber 8TC / DH Labs Interconnects

Thank you,
Joseph
joseph54
I purchased two of these amplifiers and they both have the exact same problem. They have been repaired under warranty and then repaired for the exact same problem several times each for the protection circuit issue. This problem is an engineering issue that NAD has simply swept under the rug and refused to address. Replacing the protection circuit board will work for a while but it will simply fail again with no rhyme or reason. My advice to you is get it repaired then trade or sell it for whatever you can get out of it. Other NAD amplifiers and products work just fine but this is a problem child that NAD has chosen to simply ignore. I love NAD products in general and own several of them but this amplifier is Not Always Dependable. When it does work however it is fantastic and sound quality superb. 
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