Since upgrading to FW 3.3 (including the final release version) I have detected a distortion or fizzing artefact on the front headphone output (only) whenever I check Headphone Space. It is there 100% of time regardless of any combination of Kemper settings, guitars/pick ups, cables or headphones. I have reported it to Kemper Support but the response so far is they can't hear it in my sound samples I provided.
Below is link to a sound sample. All the open G string notes and the E chords are the exact same samples repeated in my DAW and re-amped through the Kemper with Headphone Space alternately switched off & on. I have added a voice-over to indicate when it is off or on. The sample was re-amped with all Stomps, Stack, Effects and Pure Cabinet off. Input and output LEDs were lighting up just green on the peaks. I turned the Space setting up to 10 for the recording, but I can notice it from around 2 upward at reasonable headphone volume. Interested to know if anyone can hear this on my sample or on their own Kemper headphone output. On my audio sample you probably won't be able to hear it through computer or small speakers, so you will need headphones or decent monitors at a reasonable level.
Cheers
Tom