A noticeable hum in the phono when not playing could be eletromagnetic interference (EMI) caused by nearby power transformers. I had this problem recently caused by nearby outside air conditioning/heating units and other nearby electric devices with power transformers. Proximity of phono/pre-amp to power amp transformers is a common scenario for this. The solution is to add distance from phono gear to any nearby power consuming electric devices. Pops/clicks could be related to this, but not sure. The hum itself is a clear problem to address and see what happens.
In my case, I was able to eliminate the hum completely by placing my low level phono step up pre-amp inside rolled up mu metal foil and adjusting the location somewhat. Mu metal foil is inexpensive and designed for this purpose.
In any case, look for nearby devices with power transformers and try adding distance between your phono section and that device and see if hum level decreases or changes with location. That would at least help identify the source of teh problem. How to resolve from there would depend. If the phono pre-amp is integrated into the same box as other amp componenets, it could be an inherent problem or design flaw that would be tougher to resolve. I do not recall if you use an outboard phono pre-amp or a phono pre-amp built into a pre-amp or integrated or receiver perhaps?
In my case, I was able to eliminate the hum completely by placing my low level phono step up pre-amp inside rolled up mu metal foil and adjusting the location somewhat. Mu metal foil is inexpensive and designed for this purpose.
In any case, look for nearby devices with power transformers and try adding distance between your phono section and that device and see if hum level decreases or changes with location. That would at least help identify the source of teh problem. How to resolve from there would depend. If the phono pre-amp is integrated into the same box as other amp componenets, it could be an inherent problem or design flaw that would be tougher to resolve. I do not recall if you use an outboard phono pre-amp or a phono pre-amp built into a pre-amp or integrated or receiver perhaps?