I'm speaking of one of these.
Not too sure how many times I've seen these attached to the back of a 2BLP-pro balanced input to accommodate an unbalanced preamp (older 2BLP-pros only had a 1/4 balanced input, more current ones provide a dual input 1/4/ XLR socket) , the amp may sound fine but will get very hot in no time at all, even with headphones.
Hmmmmm. I wonder if the reason it gets hot is because the whole case runs hot?
I assume it does not get any hotter than the case?