"Amplifier Noise Floor" and hum acceptable?

I recently purchased the Parasound A52+ (5 channel amplifier, 180 wpc all ch driven). Initially I loved it and had no issues. About 2 weeks in however I was sitting around quietly and noticed the dreaded 60 hz hum. I get up close to the speaker midrange driver (Focal Aria 936) and there it is blaring at me. It is present in all 5 speakers I have connected. Everything is connected on a single dedicated receptacle with a power conditioner.

Trouble shooting.. the hum is not affected by volume control on the preamp. When I have removed the XLR cables to the preamp and ONLY have the speaker cables and the power cable connected... it hums. I did recently change my receptacle from a stock to a Hubbell but I don't think this would affect it. I upgraded my power conditioner too to see if that would do anything (I didn't think it would) and it did not. I switched the parasound out for a class D amp (120 wpc) and there was almost no hum. I switched it out for another class AB amp (140 wpc) and there was a hum but about half the volume of the parasound. 

So here's the gist.. when I emailed parasound tech support there are 2 things he said that I thought were noteworthy. One, he states that it is typical and normal to have some hum that close to the speaker baffle, i.e. within 1 foot of it. Second, while I asked for help he ultimately just said "I think you are just hearing the amplifier noise floor".

Three questions I pose to the community. 
Is it normal to hear a hum next to your speak baffle?
Is it acceptable and normal to be hearing the "amplifier noise floor"?
What can I try to lower this noise floor? I thought about connecting a ground wire between the chassis of the A52 and my power conditioner as the next step...

Thanks in advance for input.
OK Try this.....this worked for me..I have no reason why. I tried dehummers and I have a power conditioner. Still slight hum was there.

Take the faceplate off and remove completely the screws holding the outlet to the box. Then pull the outlet out slightly to where the metal frame of the outlet is not touching the box. Now see what happens. When I did this, all my humming went away. So I placed a small rubber washer between the box, where screws go, and the outlet and purchased plastic screws to hold the outlet in place instead of the metal ones. Worked like a charm
It is 2021, any audible amplifier noise floor and hum is unacceptable to me!

I put my ear on the twitter and hear no audible noise or hum.

Your Parasound amp has a ground loop problem IMO.
@jwl244,                                                                                                                                OK. When you changed your receptacle to the new Hubbell did you cheek the Hubbell for phase. If you reverse the hot and the neutral on the receptacle by mistake, it could cause a hum. BTW: The faint hiss from the tweeter, is the amplifier gain just lower the gain knob on the back of the amp. Hope that help. Mike
@ditusa thank you for that. I will have to check on what you said. The faint hiss I don't mind so much but thanks for that knowledge as well!