Wiim Ultra sub out creating a hum

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If I connect my Ultra to just my RSL 10e sub - nothing else connected to the Ultra - I am hearing what at first I thought was a ground loop. So I put the Ultra and sub on a powerstrip that had nothing else plugged into it. Still humming. If I move the Ultra side of the sub cable to either line out port, I get music out of the sub (albeit just lows of course) with no hum. Put it back to sub out, the hum returns. Speakers are working fine, for whatever that is worth.

I've tried a factory reset on the Ultra, reran setup with just defaults, and nothing changed. Sooo... bad Ultra sub out port?

Incidentally, all was working fine until today. I did some rearranging in my office and the sub had to move so it was unplugged, moved, and plugged back in. And that's when this started. The Ultra and other cabling was not altered until I unplugged everything except the sub cable and power for troubleshooting. I really cannot think what it could be but a bad port. I thought I would ask before opening a ticket with Wiim in case I forgot something obvious, as I am rather new to both Wiim and subs.

I purchased this through Crutchfield, but I have since found out a local shop carries Wiim. But I imagine it is Wiim I will need to contact for a claim. I appreciate any advice before I submit a ticket.

Thanks.
 
Since Ultra has 2 pin in the power cord, I would flip the plug and see if that resolves the hum issue. If you have a amplifier to drive the main, do the same thing to see if that helps.
 
Is there hum only or bass plus hum?
I do not think any music, only hum, comes through when connected to sub out. The hum is pretty loud but I cranked the sub as much as I could stand and heard only hum.

Since Ultra has 2 pin in the power cord, I would flip the plug and see if that resolves the hum issue. If you have a amplifier to drive the main, do the same thing to see if that helps.
I did not think to mention it but did flip the Ultra plug and it made no difference. Both the sub and the amp have polarized plugs and cannot be flipped.
 
But I imagine it is Wiim I will need to contact for a claim.
Actually, you'd have to claim with your contract partner first, which is the seller.

I do not think any music, only hum, comes through when connected to sub out. The hum is pretty loud but I cranked the sub as much as I could stand and heard only hum.
As a counter check, you can also connect the monophonic sub out to your power amp or active speakers, if you happen to use one or the other. The maximum output voltage of the sub out is the same as that of the line output. What are your subwoofer settings in WiiM Home app? How did you set up the 10E? Have you set low pass crossover frequency dial to bypass and connected the Ultra to the LFE input?

What about the suboofer cable? Have you been able to check this?

Sending feedback to WiiM through the WiiM Home app cannot hurt in any cases.
 
Actually, you'd have to claim with your contract partner first, which is the seller.


As a counter check, you can also connect the monophonic sub out to your power amp or active speakers, if you happen to use one or the other. The maximum output voltage of the sub out is the same as that of the line output. What are your subwoofer settings in WiiM Home app? How did you set up the 10E? Have you set low pass crossover frequency dial to bypass and connected the Ultra to the LFE input?

What about the suboofer cable? Have you been able to check this?

Sending feedback to WiiM through the WiiM Home app cannot hurt in any cases.

I will contact Crutchfield where I bought it, then.

I don't think I have an RCA to binding post cable for the power amp, but will look though my box of cables and try that if I do. My Wiim app settings for subwoofer are currently at factory defaults, other than enabling it after the Wiim factory reset as the default is off. I was using LFE in and bypass mode on the 10E. During troubleshooting I did try adjusting phase and the sub crossover but the hum persisted, albeit somewhat quieter when the LPF is set to low frequencies. The cable is about a week old, Helios brand. And as I said everything was working until I moved and hence disconnected and reconnected the sub. I cannot imagine my activity included anything that would fry the port, but I may be ignorant about it.

Thanks for all the ideas. I think I will see what Crutchfield says before I contact Wiim. I believe everything is still under warranty, so hopefully it can be resolved quickly.
 
I will contact Crutchfield where I bought it, then.

I don't think I have an RCA to binding post cable for the power amp, but will look though my box of cables and try that if I do. My Wiim app settings for subwoofer are currently at factory defaults, other than enabling it after the Wiim factory reset as the default is off. I was using LFE in and bypass mode on the 10E. During troubleshooting I did try adjusting phase and the sub crossover but the hum persisted, albeit somewhat quieter when the LPF is set to low frequencies. The cable is about a week old, Helios brand. And as I said everything was working until I moved and hence disconnected and reconnected the sub. I cannot imagine my activity included anything that would fry the port, but I may be ignorant about it.

Thanks for all the ideas. I think I will see what Crutchfield says before I contact Wiim. I believe everything is still under warranty, so hopefully it can be resolved quickly.
How long is your cable and is it coiled up?
 
Good point.

Even a brand new cable may break during plugging and unplugging, if there was a defect in manufacturing.
 
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My unit was within the Crutchfield return period, so after walking me through pretty much all the things listed above and a couple others, the rep decided they would replace it rather than using a Wiim/Linkplay warranty. Why, I do not know, maybe just to avoid the delay and hassle. The new one should be here Wednesday, and hopefully that resolves it. My bookshelf speakers do not go very low and I miss what the sub filled in. I am not a heavy bass listener but it really filled out the sound once I got it tuned nicely.

Two things he had me do that I had not thought of at all... first was to see if the hum continued between tracks. Which it did. I guess his thought there was to try and tie the hum to load on the cable. The other thing he wanted me to try was hooking some bare wire between the Wiim phono ground post and the sub ground. Unfortunately I did not have any bare wire handy, so he let that go. He thought what had probably happened was some strain on the sub out jack that led back to a circuit board inside and induced a micro fracture on the board. He said he has seen this happen (with more than just the Wiim). I am normally pretty careful with such things, but I suppose it is possible. Anyway, they are replacing it.

I have to say dealing with Crutchfield has been a pleasant experience, both this and some other purchases. Fast, professional, and happy to help resolve things when there are problems. I like to support my one local shop when I can, but Crutchfield will probably get anything else.
 
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