Building the Audio Note Kit 1 SET amp...

I will say a Mi Sheberakh prayer of healing for the amp tonight.

Hi, Guys,
Well, no joy yet. I replaced the driver board with the one that Pete sent me but it doesn't resolve the distortion issues. So I have packed up the amp and will ship it out to Pete in Florida tomorrow. He promises to get to the bottom of this.
I should mention that both Pete and Brian say they've never seen an amp behave this way. Usually it either works brilliantly or it fails miserably due to a build issue, as in "terrible noise in one channel," "really bad hum," "no sound at all" or "bursts into flames." This whole "sort of works" thing is just bizarre.
I'm sad not to have ironed this out on my own but it may just require someone with the required debugging expertise being able to get their hands on the amp in person. Pete should be that guy.
I'll update you when I know something.

Hi Reb,
Pete is just the nicest man around; really talented, and humble as well. I know he will do it for you.
As a sidebar, I have to say that on my efficient horn speakers, this amp is quieter than 3 other SS amps I tried. That was a really nice surprise, as we all know that noise obscures detail, as well as causing long term listener fatigue. When I stand with my ear to the drivers, it is really silent. Just a great amp.

I'm very curious to know what Pete discovers for this rare type of abnormality. It will be educational.

Hmm, well let's be real and not exaggerate.

Any good quality amp delivering just a few watts will clip and distort sooner than one of similar good quality with more watts, all else aside. Its just a matter of when and how. I don't think this point is debatable even really.

In this case specifically though, the experts are saying that there is something wrong and it should not be clipping and distorting as soon as it is. That makes it harder to resolve perhaps in that the issue is not as severe as many it would seem, but I don't think it accurate to say that an amp that delivers only a few watts clipping is "rare".

If one applies an underpowered amp to a task in general it might be harder than normal in practice to determine if things are working properly or not as this case would seem to support, in that clipping WILL occur sooner than in other cases.