I bought a refurbished Harman kardon AVR-430 direct from harman kardon. I have had to have it replace once already & the second one I have is not working correctly either. It will turn itself off. I have the connections right & it is in the open, so it should not have heat problems. Is HK unreliable/ Bad quality? I am upset! Should I give them another try, or go with a different brand? What would you guys recommend?