I have had my Def Tech SCIII sub for 2 years now. For the last week I have been hearing noise that sounds like wind hitting a microphone. Honestly it sounded like it was coming from the unit above me (live in a condo).

When I went to update my BD player I could hear it better so I put my ear next to the sub and the noise was there. I turned my receiver off and the noise was still there. I disconnected the LFE cable and the noise was still there. Is this some kind of interference or is something internally wrong? I think something is wrong because it has been like this for only a week.

This is a new one to me. It sounds like a problem with the power supply. It may be a bad filter that is letting some AC through. When you turn it off, does it go away? Try unplugging it, leave it unplugged for a few minutes, then plug it back in.

I unplugged it and moved it to another outlet just to eliminate that possibility as well. Plugged it in with everything off and no sound (the sub light wasn't on yet either). Once I turned everything on and the sub found the LFE signal and powered on the noise came back even on a new outlet. So it is something with the sub.

I unplugged it and moved it to another outlet just to eliminate that possibility as well. Plugged it in with everything off and no sound (the sub light wasn't on yet either). Once I turned everything on and the sub found the LFE signal and powered on the noise came back even on a new outlet. So it is something with the sub.I would suspect some electronic component on the amp is failed or failing. I don't suppose it's still under warranty?

It is because Def Tech give 5 yrs but instead of just taking it in and them fixing it I always like to know what the possible issues could be for my benefit.

The noise is being generated by the speaker, right? It does it when there is no source input. Do you hear it when you are actually using the sub?

The sound is noticeable once it recognizes a signal. At that point whether or not I have the LFE cable connected to it the noise is still there. It is louder when I am watching movies at a higher level. I would need to take the power away from it then plug it in with everything else off for it to be quiet.

I believe the SC3 has an auto on circuit, so once it gets a signal, it will take a while to go back to standby. when you unplug it, you force if off. When you plug it back in, it should come up in standby. After it is making the noise, remove the input and then let it sit for 15-20 minutes. See if it goes back to standby. there should be a light that indicates whether it is in standby or on. I still suspect there is some filter circuit with a leak. This could be in the AC/DC conversion circuits or in the amp section. Either way, getting it to DT for warranty service will be the only way to get it fixed.

The lucky thing is ABT Electronics is my local store and they are authorized retailers of all the products they sell so they repair in house. I dropped it off yesterday so we will see.

Aren't long warranties a wonderful thing?

It was the low level amp, I should have it back early next week.