Speaker static/hiss?

It’s caused by suboptimal gain structure. You have way too much active gain after the volume control (this means your combined preamp and amplifier circuitry - which generates higher noise floor per extra dB of gain even if signal-to-noise remains the same), relative to your needs determined by listening level and speaker sensitivity.

I have this situation myself, with very sensitive 96dB / 2.83V Tannoys. I easily notice the signal-to-noise ratio differences between preamps. I need to keep the preamp gain below 14dB, and even at that level the preamp’s signal-to-noise ratio has to be VERY high to avoid an audible "hisssssss" at volume = 0. The ARC Reference 6 has a stellar signal-to-noise. VAC Master also excellent. Some other preamps...are not so great.

Often inserting signal attenuators (e.g. Harrison Labs) to the tube of ~ 10dB is recommended to push the noise floor down while utilizing more gain from your circuitry. However, if you have the Parasound amps, as @russ69 mentioned - turning down the gain pots should be the best solution here.

What is your gear ??

What is your gear ??
 

Parasound A21+ amp

Paradigm Founders 100F

Marantz 8805 pre amp

Bluesound Node (2021 model)

Furman SPR-20 

Dedicated 20amp service to the room with Audioquest 20amp receptacles. 

SVS SB3000 subs (four-one in each corner of the room)

some other odds and ends. 

Your speakers have slightly higher than average sensitivity. A21+ is a good amp that looks like a reasonable pairing here. That Marantz though - a 13.2 channel preamp? Holy cow! That thing is so chock full of multi-channel features they don’t even bother to list a gain spec. But that would be the most suspect component here. Maybe it has a variable or selectable gain feature you could play with? But really, the easiest solution should be to lower the gain pots on your A21+ until you reach a good balance. You're lucky to have an amp with that feature - most modern hifi amps don't (some of us get antsy about extra potentiometers in the signal path - same with balance controls). What do you currently have those adjusted to? Are they at max gain?

Nothing to worry about. I had a amp that did the same thing.