USB Distortion Problems?

[Kenna]

Hi there, I have recently received a new power amp for my speakers. I have it connected to my Headphone amp/Dac which functions as the pre-amp, the problem is that I get a pretty loud and audible hiss/noise from the speakers, Even at at regular listening volumes I can hear it if i listen closely.

The power amp and speakers I build myself from a kit, while the Pre-amp is a Matrix Mstage HPA2 that I have used with my HD800 for 2 years.

The Distortion seems to be coming from my PC, whenever I plug my pre-amp into my PC and connected it to my amp the distortion is there and loud, I plugged the MStage usb cable into my phone using a type c adapter and the distortion is basically unnoticeable. I tried plugging the cable into my Predator x34's usb pass through but it made no difference, the problem seems to come from my pc itself, I also tried using different usb ports on it but distortion was still present.

My question is how do I get rid of this distortion, I was thinking about buying a shielded cable, but I'm doubtful if it will help, since the problem may be coming from inside my PC. 
Please Help, I really need to be able to use my PC with my speaker system.

 

 

 

[emosun]

the only solution i can think of is an oldschool solution which is to turn the source up as loud as possible (the volume slider on the pc) then turn the volume on your amps down which will sometimes reduce hiss.

[Kenna]

Doesn't work, power amp has no volume control that is what the pre-amp is for and even with the pre-amp volume knob all the way to mute, the distortion hiss from my speakers is still there.Changing it in windows doesn't help as well.

 

[tzxazrael]

so if i understand right...

 

when you plug the pre-amp into the pc, it's very hissy.

 

when you plug the pre-amp into other devices, with the setup otherwise the same, it's not hissy.

 

is that correct?

 

if so, the problem is definitely from the PC. 

 

consider: windows has -several- volume controls. the speaker in the system tray (next to the clock), and probably a volume control in whatever media program (or game or whatever) you're using.

 

i think @emosun was suggesting turn the media program's volume all the way up, and turn the windows volume back down... this might reduce the hiss.

 

not sure if this is what you already tried.

[Kenna]

I tried that and it didn't work, the thing is though that when I plug my HD800 into the front 6.35mm input of the Mstage there is no noticable distortion when the Mstage is connected to my PC. I use a RCA cable connected to the Mstage's rear secondary output to connect to my amp.

 

[EsaT]

15 hours ago, Kenna said:

I tried that and it didn't work, the thing is though that when I plug my HD800 into the front 6.35mm input of the Mstage there is no noticable distortion when the Mstage is connected to my PC. I use a RCA cable connected to the Mstage's rear secondary output to connect to my amp.

Is everything connected to one outlets?

And what about grounding of it?

 

And if it's coming from PC USB isolator might help.

[Volbet]

Hiss/noise would indicate a power problem, so getting an isolated (whatever the fuck that's good for) USB cable might not help anything.

 

Although, trying a different USB cable might be a solid first step. As would trying to plug the USB cable into a powered hub rather than directly into the computer.

 

If neither of these things work, which I doubt they will, you might just have a grounding issue on your hands.

Using your PC and speaker amp simultaneously might just create a ground loop.

Try moving moving one of the two to a different power outlet and, if possible, move them to two different breakers.

[Kenna]

Was thinking about maybe getting a usb noise filter,Something like the AudioQuest JitterBug or Ifi Silencer.

I did try different power sockets but it didn't seem to help. 

[Kenna]

I fixed it, I had to run a 3 metre extension cable to a power socket in another room and it fixed it, the other power socket in my room also had distortion issues.

 

[EsaT]

13 hours ago, Kenna said:

I fixed it, I had to run a 3 metre extension cable to a power socket in another room and it fixed it, the other power socket in my room also had distortion issues.

Cause is likely some kind grounding issue.

If ground reference is different in different outlet, or there's mix of grounded/ungroudned sockets that can create kind of leak currents in audio equipment cabling causing interference.

(cell phone isn't ground referenced, so it isn't affected by those)

[Kenna]

Unfortunately after just under 24hrs the distortion problem has came back, even with my amp plugged into a different outlet. I know the problem is definitely from my PC, since i can plug my laptop and into my Mstage and the distortion is gone.

Just then I briefly restarted my PC and the distortion problem seemed to go, but after about 5-10min it started coming back.

I'll turn my PC off for the next hour and then restart it to see if that does anything.

I may end up looking into a USB noise filter after all. 

  

[KuJoe]

Nevermind, didn't pay attention to the connections you mentioned. My bad.