Klipsch 5.1 Hissing/Backround noise

[Bulldog]

I've got the Klipsch 5.1 ProMedia PC speaker setup. Recently I started hearing hissing/static/ popping/noise coming from all the speakers no matter if its plugged into the soundcard or not. Tried different power cords, different power outlets. Anyone have any ideas? Does it sound chink cap related?
Sometimes it will go away for a while and they sound awesome, then the static will come back and stay for a while. Power cycling does nothing.

[Krankshaft]

Re: Klipsch 5.1 Hissing/Backround noise

Check for cracked solder joints on the main pcb first.

[Bulldog]

Re: Klipsch 5.1 Hissing/Backround noise

could not see anything cracked or any obvious leaking caps

[Krankshaft]

Re: Klipsch 5.1 Hissing/Backround noise

Did you try freeze spray to look for thermal intermittent ICs?

[Bulldog]

Re: Klipsch 5.1 Hissing/Backround noise

come again?

[weirdlookinguy]

Re: Klipsch 5.1 Hissing/Backround noise

Freezing spray is something you spray on circuit boards. As the name implies, it freezes the particular part of the board you sprayed. If you spray a certain part of the board and the problem goes away temporarily, you know that your failure is due to either a cracked solder joint or a marginal component that isn't doing its job when it heats up.

[Bulldog]

Re: Klipsch 5.1 Hissing/Backround noise

It'll do it right when you turn it on. But i see what your saying. It could heat up instantly.

I think its in the AC to DC allowing AC to leak thru causing noise?

Where can I buy this spray?

[Krankshaft]

Re: Klipsch 5.1 Hissing/Backround noise

Before that spray any mechanical POTs with Deoxit contact cleaner.

Scratching sounds can come from this.

[berniedd]

Re: Klipsch 5.1 Hissing/Backround noise

You could also use the eraser tip of a pencil to rock components on the board gently back and forth. You've identified the bad part when motion causes the symptom to appear/disappear.

[Toasty]

Re: Klipsch 5.1 Hissing/Backround noise

Any word?

[Maxxarcade]

Re: Klipsch 5.1 Hissing/Backround noise

Is this the system that only uses analog inputs for each channel (no digital decoder/SPDIF input)?

I'm wondering if there is a volume control IC that is getting noisy. That would probably be the only thing that is common to all amplifier circuits, since there is no digital processing IC.

Could also be the power supply, though it would probably be constant, and worse when cold if that were the case.

[techer]

Re: Klipsch 5.1 Hissing/Backround noise

I have seen this before but I think it was the volume control POT. Its a surface mount type and I have not seen around like it for sale so you may have to get the volume control board from klipsch direct.

[rhomanski]

Re: Klipsch 5.1 Hissing/Backround noise

On mine it was a transistor going out, inside the sub box. It also has several known problems with heat related failures of other components. Most will mount two fans to protect these components. A google should still bring up the procedures.

Regards. Ron.