NAD 7140 repair-HELP

I recently picked up a NAD 7140. When plugged in it lights up and the relay audibly clicked, but no sound from any source or from headphone jack. I found the preamp does work with another power source. I understand that NAD products have had reliability issues. So, is anyone out there aware of a common fail in this line of receivers, where is the first and best place for me to check? I will try DIY repair as well with some direction, where to start? I don't see any obvious leaking caps or fried resistors. I also cleaned pots, buttons, and connections with electrical cleaner. One last thing, when I opened it up there were two slow burning fuses burnt out, neither being the main power fuse. I replaced them and they held when I turned the unit on. I may sound like I know what I'm doing, but I am brand new at tackling a self diagnosis and fix. I do find it a challenge that I want to take on and learn something along the way. I have scoured the internet for answers without any success.  
I hope someone in this community can help and give direction.
Thank you!