Does this happen on all HDMI ports? Something to check. Otherwise, you are better off sending it to Krell for repair.
KRELL 707, HDMI input and output (including audio and video) does not respond!
Fault description: My KRELL 707, HDMI input and output (including audio and video) does not respond! Whenever HDMI input is used, the machine display shows waiting for audio, and the TV shows no signal input. However, the optical front and coaxial input are normal. I found that some 707 users on the forum also encountered this problem. Is it a common problem? How to solve it? Thank you