Audigy SoundBlaster SB1550 Distortion and Noise

Hey guys!

I just got this DAC/Amplifier board for my PC and it has low amplitude noise on the right channel for the Line Out 1.
On top of that, it has distortion above 70% volume.
There doesn't seem to be any blown caps or anything. Nothing burned.

Anyone got any clue what the culprit is?

It has these ICs:
Creative CA10300-IAT LF
Cirrus Logic CS4382ACQZ
IDT Tsi381-66ILV
TSI STAC9750XX
And a couple of ST 4558C

Thanks!
 
There is a wiki that may help identify what the ICs are for: Sound Blaster Audigy - Wikipedia

Other than that, maybe googling with turn up something useful.

Even if you figured out where the problem is, doesn't mean you could get parts to fix it. May not be worth fixing either considering some of what it says about them in the wiki.

Also, with a rough idea of what the chips do, you might be able to trace digital signals with a scope (if you have one). Possibly the problem is after the dac and somewhere in the analog output circuitry. A scope would also be a good tool to take a look in that area.
 
There is a wiki that may help identify what the ICs are for: Sound Blaster Audigy - Wikipedia

Other than that, maybe googling with turn up something useful.

Even if you figured out where the problem is, doesn't mean you could get parts to fix it. May not be worth fixing either considering some of what it says about them in the wiki.

Also, with a rough idea of what the chips do, you might be able to trace digital signals with a scope (if you have one). Possibly the problem is after the dac and somewhere in the analog output circuitry. A scope would also be a good tool to take a look in that area.

Thanks for the link. I'll look into it.
I changed one of the OP-amps (4558), and it didn't help at all.
Could it be a bad ground connection or something?

I used to have a cheap oscilloscope but it died about a week ago.