Hitachi Woofer amp Crackling and noise

[Bigg_T]

Hello,

I have a Hitachi HTS5 10" 150 Watt powered subwoofer. I'm trying to isolate the problem with the amplifier.

When I turn the volume up on the amp (sub out level) it crackles followed buy intermittent blasts of noise and further crackling. When the unit is operating at low volume (sub out) levels it seems to work without problem. As soon as I touch the volume dial either up or down it crackles quite loud.

Turning the crossover frequency works and does not seem to activate the crackling.

I'm wondering is this a capacitor issue or a an internal grounding issue? Not being able to hold up enough charge to output the higher levels?


Or would it be that the sub is blown? I wouldn't think it's the sub because it can produce clean high level output when the sub out level is low but the source material is turned up.


Any help would be greatly appreciated.

Tom