Help Solving JL Audio Sub Noise Issue

[nicoff]

I have a pair of F113 v2 subs. I just noticed a very faint but steady noise coming from both subs. This only happens when the light dimming switch on the sub is on. Both subs do the same. The noise is steady (does not increase with volume). However, when the light dimming switch of the sub is off, the noise goes away.
Has anybody experienced this?

[Tubes]

Is it a 60Hz hum?

[nicoff]

Is it a 60Hz hum?

Quite possibly.

[Tubes]

Might be something as simple as a grounding problem.

[nicoff]

Might be something as simple as a grounding problem.

But I wonder why it is not happening all the time? When the sub's dimming light switch is off, the noise disappears. I will have to try different outlets and see if I can replicate the problem. Thanks!!

[Andik777]

Hello nicoff, I had a similar problem, I found the solution, it was an HDMI cable, (which I had connected to my blu ray) I called my TV provider and in the decoder they put a filter. Problem solved Please, if you have any HDMI cable disconnect it to see if the hum disappears. Luck. Below the filter image

[nicoff]

Hello nicoff, I had a similar problem, I found the solution, it was an HDMI cable, (which I had connected to my blu ray) I called my TV provider and in the decoder they put a filter. Problem solved Please, if you have any HDMI cable disconnect it to see if the hum disappears. Luck. Below the filter image

Thank you Andik! Will definitely look into it!

[nicoff]

Well, it looks as if the cable box is not the problem. I disconnected the cable box altogether and I still get the noise.

Moreover, even after I turn the sub off the noise continues for a few seconds decreasing in volume until it stops. It sounds to me that the dimming switch could be connected to an internal part (probably a capacitor) that is going bad and the noise comes from that part.

I have contacted JL Audio and I am waiting to hear back.