static in headphones when volume is turned up (clipping?)

Hello,

I noticed that I hear static in my Beyerdynamic DT770 32 ohm headphones (from the Kemper stage) only when the volume is turned up and when I strum or pick the guitar strings. This happens when coming from headphones out on the Kemper, as well as when coming from the "main monitor" 1/4" out jacks on kemper -> headphone amp -> headphones. I first noticed it when I would turn the headphone volume up on the Kemper from the output menu. I figured it had something to do with clipping, so I ordered this headphone amplifier. I just tried it this morning, and I noticed the static again when I turn the volume up on the headphone amp (not the Kemper). Then I thought that maybe it's a problem with my headphones, and I plugged my computer headphones into my headphone amp and turned everything as loud as it would go, and no static. That seems to narrow it down to the Kemper or likely something I'm doing wrong with the Kemper. Does anyone have any insights into this?

edit:

If it's digital distortion or clipping, why would it only happen when the headphones volume is turned up? It's possible that it's also there when the volume is not turned up and I'm just not able to hear it, but I really don't think that's the case. There's no static when I'm outputting to my FRFR monitor ("main monitor" out -> FRFR amp) no matter what volume/level at which it's set. That just gave me the idea to plug my monitor cable into my headphone amp (edit: that did not help).

edit 2:

Now I'm wondering if it has to do with an impedence mismatch (Kemper 330 ohm / headphones 32 ohm) Kemper appears to be 33 ohm headphone out Wrong again, kemper specs show 32-600 ohm impedence

edit 3:

wondering if something is wrong with the headphones

Thanks!

Frank

my headphones: https://www.sweetwater.com/store/detail/D…xing-headphones

Update: The current assumption we're working under is that the headphones have too low of impedence, and Sweetwater is exchanging my headphones for the DT 770s at 80ohm impedence. I'm not sure if this is correct though because the Kemper specs show between 32 and 600 ohms.

We also tested with some sports headphones I have at home which appear to have about 35ohm impedence, and I could hear some static in them as well when the volume is high

Another update: I received the Beyerdynamic DT 770s with 80 ohm impedence and the static was noticably better, but it's still there. I'm considering exchanging those again for the 250 ohm ones. Apparently though I may need a headphone amp with those.

If the problem really has to do with the impedence, then it's too bad that Kemper is not properly communicating that in their specs and manual. Although, by the lack of contribution to my question, it appears that very few people are running into this or are not using the headphone jack