Cary Audio SA 200.2 SE power amp (latest version)

I had the Cary Audio SA 200.2.  I had the same buzz problem.  It was present on both channels.  It did not increase with volume.  It could be heard whether or not my Cary SLP-98P was powered up.  It was coming from the amp itself.  It could not be heard when music was playing.  The problem was once I knew it was there I couldn't unhear it, and it became bothersome.  

I contacted Cary for help.  I got this response focusing on the 3 wires connected to the PC board:

"We have learned the manufacture of these connectors used oil film coating on them for storage.  When the connectors are plugged into the board sometimes the metal doesn't make a good connection. To make a better connection we would pull the connectors off and push back on once or twice. By pulling off the connector and pushing back on the (2) metal pieces scrape and dig into each other making a very good connection. There are (2) amp modules. So one would have to do this for both channels."

I tried that.  It made no difference at all.  I eventually sold the amp.

Apart from that significant issue, the amp sounded very good.  If it weren't for that I'd likely still be using it.

This is a bummer learning more than a few of you experienced this humming issue on the non-ES and newer ES models of the SA-200.2  Mine was dead quiet, and reluctantly sold it.  What's concerning here is the initial response from Cary. May need to escalate it further.    If I still had my amp and it did this, it would be worth pushing on Cary Audio to send a repair white-paper with instructions for local service techs to help isolate, test, and fix this so called "oil films coating" connector issue. There may be a better way to get this coating off of the connectors, IF this is truly the root cause of the hum problem.   

At one point I thought about re-trying one of the newer ES amps yet after reading this, I'll wait.  One of you here (remaining ambassadors) who still owns one of these amps might want to reach out to owner and president Billy Wright to get him to come up with a solution. The hum noise is unacceptable for new amps.  Worth fixing locally vs. shipping back and forth, nice sounding amps.

@garyalex 

Yours is different. Yours is the original version of the SA 200.2, mine is the newer current SA 200.2 ES model. I sent it back to Cary and it’s quiet there when they put the amp in their listening room, so they couldn’t figure out what went wrong and so there’s nothing to be fixed and repaired. So they sent me a brand new SA 200.2 ES and they took my other amp in on a trade and they made me pay $1500 plus shipping towards a brand new amp. 
 

I have received the brand new amp 3 weeks ago and so far it’s been working flawlessly, no loud buzzing. It’s quiet. Wierd huh? 

@dilatante Yes, it is weird. Did you by chance plug the new amp into the same plug as before, or a different plug, and/or possibly different routing of cables too?

Sometimes having two different power cables on top of each other or one of them close to a set of non-shielded interconnect cables can produce a hum too.