It IS holiday time here in the U.S., so perhaps they've just been busy.
At the risk of sounding silly, have you checked the 2.5A fuse for the affected tweeter? I can't tell you how many times I thought I had blown a tweeter (on my old 2.2/Rs), only to find that it was a simple fuse issue. With a previous buggy amp, I'd sometimes have a channel go out, so had to do the whole cable-swap/elimination thing to debug the problem.
I only ask because you did not mention doing any of that in your original post.
I find that with the proper 2.5A fuse installed, it's actually pretty hard to trash the tweeter. YMMV, of course.
At the risk of sounding silly, have you checked the 2.5A fuse for the affected tweeter? I can't tell you how many times I thought I had blown a tweeter (on my old 2.2/Rs), only to find that it was a simple fuse issue. With a previous buggy amp, I'd sometimes have a channel go out, so had to do the whole cable-swap/elimination thing to debug the problem.
I only ask because you did not mention doing any of that in your original post.
I find that with the proper 2.5A fuse installed, it's actually pretty hard to trash the tweeter. YMMV, of course.