trhx

Sometimes when I connect my XLR outs to my UI24r mixer, I get noise going up to about -24 or so on one channel and a little bit of noise on the other channel. When I switch the cables only on one end, all the noise goes away. I've seen this several times over the course of a few months. Obviously, the fix is easy but I'd love to understand what is happening here. I wouldn't think that the mixer cares or even knows which Helix output is going into which mixer input. The inputs on the mixer are stereo linked, so I can try to unlink just to see if that makes a difference. Any other educated theories are welcome. Also, I realize that any issue could be with the mixer rather than the Helix, so I guess I should post in a UI24 group, too.

I checked the ground lift the last time it happened, but that didn't make a difference. I can't say for sure it isn't a problem with the mixer. Since I have a feeling it's related to the stereo link, I can test with my stereo edrum kit and report back next week.

I have stereo XLRs going from Helix straight into 2 inputs on my digital mixer (UI24r) and set the gains to hit about -18 to -12. The 2 mixer channels for my guitar are stereo linked, so the gain levels are the only independent settings. There have been a couple of times where I get a signal of about -24 on only one input while not playing. So far, the fix has been to switch the cables at one end. Doesn't matter whether I switch at the Helix or at the mixer - both signals are zero after I make the switch. Obviously, pretty easy fix (and I can label my cables for specific channels) but I'd like to understand why that happens. Seems like a polarity thing, but I'm just not quite getting it. Can someone tell me why this happens? Thanks.

Some amps seem more affected than others. Eg, the Soldano OD amp has a more noticeable hump than the PV Panama high gain amp. However, the Soldano hump is not very noticeable with the full band playing, so I've decided not to obsess over it if I keep that amp as my primary. For the same reason, I didn't try it with a volume pedal block. Maybe I'll get a wild hair and do it at some point. Thanks for the responses.

I have the built in exp pedal assigned to change the drive and volume of an amp (eg, Solo Lead OD). The volume is set to counteract the gain volume, so gain is higher at toe and lower at heel while volume is higher at heel and lower at toe. The main reason I do this is to be able to have some flexibility with the drive level between my minimum and max drive setting. It's also easier to hit the large pedal than a footswitch while I'm singing. Getting the volumes to match at the heel and toe positions is easy, but there is a volume hump at around 40%. I've tried using the master volume and channel volume, and the master seems to make a less noticeable hump. I know master will alter the tone more, but that's ok in this case. I don't know if the pedal is linear or logarithmic or if that would make a difference. Searching for an answer, it occurs to me I haven't tried controlling the volume with a volume pedal block instead of amp channel or master volume, so I'll try that and report back. If anyone has other suggestions, please let me know. Thanks.