I like tomic601's advise of checking connections.
Besides that a balanced transformer in the power cord, such as the one Core Power makes may be excellent on the streamer, and it will isolate.
For the amp, a heavy duty outlet such as Hubble is necessary. Jena Labs has cryo treated ones for a good price. A high quality surge protector at the breaker box such as The EP2050 would improve the sound of the entire system, and give protection. A cheaper one would be one from Eaton. Will protect but not improve the sound. The right power cord is essential to best sound. Try a few... like four or five.
I also second the Nordost devises. I have a few, but they are not cheap. There are a few passive/plug in types out there.
Besides that a balanced transformer in the power cord, such as the one Core Power makes may be excellent on the streamer, and it will isolate.
For the amp, a heavy duty outlet such as Hubble is necessary. Jena Labs has cryo treated ones for a good price. A high quality surge protector at the breaker box such as The EP2050 would improve the sound of the entire system, and give protection. A cheaper one would be one from Eaton. Will protect but not improve the sound. The right power cord is essential to best sound. Try a few... like four or five.
I also second the Nordost devises. I have a few, but they are not cheap. There are a few passive/plug in types out there.