Smooth555

Same issue here. I opened a ticket on it and will update as I hear more.

Same issue as a couple others when running Helix 2.8 out the XLRs. I reset the global settings for Line output on the XLR after the update. However, now when I turn on, regardless of it saying it's set to Line in the Global settings, it puts out a Mic level signal. If I toggle to Mic and back to Line I get my 14db back but it requires a manual adjustment each time I turn on.

I've just had this issue, I think. I didn't open it up yet to investigate, but while playing with it, I heard a loud crack. The pedal is now slightly not square, not much side to side play, but I can see the bolt from the side shifting around as I rock the pedal from front to back by hand. Seems like, from this thread, this isn't too uncommon an issue. Mine is only about 3 months old, never gigged and most of my playing is done barefoot in my basement - so not too heavy duty with my stomping... I've opened a ticket and we'll see where things go. I bought from Sweetwater so I've also got that warranty option as well - not sure which is the better route.

I'll throw my results in because I hate when there's no resolution on these kinds of threads. L6 basically said that the noise was normal with my Helix LT. I ended up buying an EbTech hum eliminator and that removed my ground loop issues with the effects loop and send return. I still get some RF interference that's amplified on the higher gain settings of my Mesa Mark V but 4CM now works. On those high gain patches, I use a hard gate to kill any additional buzz and that's been quite enjoyable. This ends up being a lot of cables for what was supposed to be a simpler set up (I've got short patch cables between the LT and the EbTech, longer cables to the amp and EbTech, but throw in that I am also using a voodoo lab control switcher to midi control my Mesa Mark V, with midi cable and 4 1/4" into the switches on the back, there's a lot going on) but since I don't play out so much, it's not so bad and it does sound really good. I split my playing time between going through the Mark V and going direct through some Yamaha studio monitors. It's totally dependent on my mood of the day and what I feel like playing, even if I think the amp is still 5% better than the models in the LT. Unless I'm doing rapid fire AB tests, which aren't totally fair to the LT, it more than produces excellent tones that are inspiring to play. The Helix has completely replaced my pedalboard and the footswitch for my Mark V with the exception of a digitech whammy (the pitchshift is just not as good/clean/clear). I still have GAS for a Friedman Dirty Shirley to compliment my Mark V, but I'm also thinking about getting an FRFR solution like a DXR10/12 or Powercab for the helix because it's very good at the pallet of tones that the Mark V doesn't do so well (mid-gain, vintage voicing, M style types of things and some of the different cab types).

Please let us know what comes of it. I’m trying to run my Helix lt with a Mesa Mark v in 4cm and having the same noise floor issue. I’ve got the ebtech hum eliminator solving a ground loop in the effects loop, but the hiss is still there. The hiss is there on all channels but particularly prominent when I go to channel 3. I’m managing with a hard gate, it’s not so bad while playing, but significantly noisier than my pedals into the amp.

It’s not just you. I got a helix LT 2 week starts ago and have been experiencing similar problems when running 4cm with my Mesa Mark V. I get a ton of hum on channels 2&3. that drops if I unplug the usb but there’s still enough to be annoying. Running direct guitar to amp with no helix is dead silent on all channels. I’ve not had problems previously with just pedals powered by a one spot (which is used on pedals before I put and in the loop). I was trying to diagnose with a 2 to 3 prong adapter but that made no difference when trying on both the helix and the Mesa. However, while trying that I noticed that the hum is there even with the helix off and unplugged from an outlet if the cables are still connected. Weird. Pulling the USB did help a lot but it’s still a problem. Channel 1 is quiet but I think the noise is still there, it’s just not gained up like 2 & 3. Would like to know if you’ve figured it out.