[MikeW]

I've got a valab dac and the resistor in the left channel has caused a "hum" in only that channel at high volumes. I replaced it with a cheap radioshack resistor as a test and the problem went away. My question is what happend to this resistor (it's a PRP 330 Ohm). I did not realize resistors could "go bad" like this? Did i overheat it? just a bad part? it's strange.

 

[Steve Eddy]

May not have been the resistor. May have been a dodgy solder joint that was resolved when the new resistor was installed.

se

 

[Juaquin]

From my (limited) experience, if they're damaged but not entirely destroyed their value has been permanently changed; it shouldn't fluctuate wildly. It was probably the joint.

 

[MikeW]

but I took the radio shack one back out and put the old resistor back and the noise returned. I resoldered it a few times and still had the noise. Hmm i wonder if I need to solder-suck all the old solder from the back of the board and apply fresh solder.