Regularly, (more regularly than I have ever seen in another POS at any other retailer I have worked for) the POS gives an error stating that the order could not process and the options are to bring up the order again, check the admin to see if the payment went through or to clear the order from our screen. I really wish someone would take the time to look into this and actually implement a fix. We can't be the only store having this problem and it's been around a lot longer than should be acceptable and it happens multiple times every day without fail.
I don't have it happen quite as often as you but I've seen it a few dozen times over the last few months.
I find I get that error a lot if there's something funky going on with my internet connection (we have a loose cable that sometimes needs to be re-plugged in). If I were you I might look into whether or not you have connection issues too.
That said, I've also gotten this error when I'm properly connected, so yeah, it would be nice if CC would figure out what the issue is, TELL US, and fix it.