My replacement PA5 is now exhibiting the same static issue. Did not use it all day…this evening, my wife let me know “it's making that noise again.” Sure enough, constant staticy white noise through one speaker, even though nothing playing from streamer, DAC in standby mode.
Will be requesting a return from APOS. After 2 faulty units, I think I'm done. Very disappointed in Topping's QC on these units.
I suggest adding a little more work to identify the cause.
Turn off the power of the PA5 and disconnect all the cables connected to the input terminal of the PA5.
The PA5 and speakers remain connected.
The only cables connected to the PA5 are the AC adapter cable and speaker cable.
In that state, turn on the power of PA5.
If you still hear a lot of noise from the speakers, it's probably a PA5 failure.
Or, even if the PA5 is normal, the noise may be unacceptable.
If your speakers are very efficient.
In that case, it is difficult to use PA5 in your environment.