Krell KAV400xi - source button issue

I just bought yesterday a new KAV400xi. It's great and sounds awesome. However I have no idea what happened but after a long listening today I observed that I can not choose a source from the front panel - the button S2 and B1 just stopped responding. But I still can choose S2 or
B1 using remote controller - no problems with that and sound still goes on great. I tried to unplug amplifier fully and check if that would help but still can't access S2 and B1 from the front panel. It seems quite weird to me. Have I blocked anything manually? What should I do? It’s not really killing me as I still have the remote to operate but would like to know if I should avoid anything? And there was no electric shock either from my side....
Later on I noticed that if I press front panel buttn B1 for let's say 5 sec. then it goes OK, I also pressed S2 foralong time and 2-3 times it went OK after 10-15 sec. of pressing the button.... With remote it is instant - no delays...


This is why mfgs. put warranties on their products.
It would be best to call Krell in CT. I doubt that there is anything that you can do to fix it, it sounds like a bad relay-switch (button) on the front panel, which would need to be replaced.
if you just bought it yesterday and it's new simply take it back to where you bought it and exchange it.