Serendipitous timing that this thread is back from the dead. 3 years later our Breville smart(ish) oven is dying. The bottom heating elements only come on when they feel like it, resulting in jeckyl/hyde slices of toast. And it's started shrieking at us. It sounds like a bad fan bearing, but we see no evidence that there's a fan anywhere in there. It's not a convection model. Nothing deep in the bowels looks fan-like. So I can only conclude that it's either haunted, angry, or in some kind of deep psychic pain.
At first we could distract it back into quiet servitude with a crisp zen slap. But after a while it needed multiple slaps. Eventually it needed one or more full-on haymaker punches, right to the midsection. Now it's dented, madder than ever, and defiant—violence no longer works at all.
The happy news: Breville has offered to fix it. It's way out of warranty, but our story must have made them feel sorry for us. I suspect fixing it will take a long time, and we don't want to be without a toaster oven (the untoasted life being not worth living, etc.). So we've ordered a new one. Same model, to test our luck. When it shows up, we'll send the old one for repairs, and when that eventually comes back we'll give it to someone.
Someone who likes toast, and doesn't mind a slight fist-shaped dent.