Most business starters make mistakes in the beginning, and even along the way. What matters is that they should learn from those mistakes and, if possible, correct their wrongs.
Otherwise, the business is going to fail.
You need more than a good product to run a successful business.
Hopefully it all works out. Like others, I remember when another amp company already mentioned first got going. There were a few issues and plenty of angry people back then. But, the company got its act together and everything seems to be going well now.
Everyone just needs to relax. If it were me, I'd get a refund and wait until everything got sorted out first. If a refund is refused for whatever reason, I'd take it up with the proper authorities. But, bitching about it on an internet forum is not the way to go.