Mark levinson 360s DAC...???

I assume the 360s is similar to my 36 which stays just as warm in standby as it does during operation.

To quote the manual for the 36:

"Pressing standby again places the No36 into standby mode, which turns the display off, turns off all outputs, and disables the front-panel controls. The internal circuitry remains powered up in order to maintain its thermal stability and optimum performance at all times."

I think this is normal for your 360s.

I owned a 360s. A warm operating temperature is perfectly normal.

HI, I confirm, also my 360s is enough warm when it is in standby.