edpauley7

No problem, and your comments and observations are appreciated. I've only used the Helix through my amp and studio monitors (unfortunately, my headphones suck). Your suggestion makes sense and I'll give that a try when I return home later today.

I haven't try it with an empty patch but will do so latter today. Thanks!

Thanks, bru58ski! Yes, as stated above, this happens regardless of what presets I use - including ones I create. Everything seems find for about 5 minutes. of playing and then the volume level drops (i.e., from 10 to 6). As I continue to play for another 5 minutes, the volume quickly jumps back to level 10. BTW, I know it says I've "just startin'" but I have 15 years experienced of using Line 6 modelers and the forums but I haven't encountered this issue before.

The volume level on my HX Stomp ebbs and flows somewhat without me touching any controls. This happens whether I playing (using different guitars) through my tube amp or studio monitors. This happens on all presets. Any suggestions?