I guess the amp need to be burnt in before it can do it best. The question is that how long should I burn-in the amp.
Around 200 hours of music playing is usual. With a brand new unit for use as a demo unit here I have a CD playing, or an FM signal playing night and day for at least 9 days before demonstrating to potential buyers. I need to point out that the volume at which you do this night and day break-in does not influence the speed nor quality of the process. There is no need to disturb the neighbours!