Am not sure why you would be unhappy with McIntosh. In less than 48 hours of posting your received a new replacement amp. Pretty good, if you ask me. You were lucky you didn't have to wait for one to be shipped in.
Poping noise starting up Mcintosh MA 6900
When I turn on the amp using the standby button, I get a popping noise that is audible through the speakers. Not loud, but can be heard. The amp is just 1 week old. I had the MA 6500 in the same set-up and liked it so much I upgraded to the 6900. The 6500 made no noise, none. Is this inherent to the design (autoformers) or is there a problem? If anyone has the same experience or has suggestions, please respond, thanks.