Regarding fuse ROTATION... I have found "DOTS DOWN" to sound the best.
My Marsh power amp has two fuses per channel. When I initially installed the black fuses, all four dots on the fuses were facing up.
Yesterday I rotated them so their position was changed 180 degrees.
My first (five minute) impression was positive, and I was not motivated to change them back. Eight hours later, during a longer listening session, I was feeling the way I did when I heard the improvement from the fuses for the first time. But the sound was even better!
My cd player has a single fuse and I am pretty sure I installed it the same way. The mains fuse on the Marsh is screwed in to a barrel...
I guess I could also rotate it and check for any differences.
I encourage everyone to experiment with fuse rotation!
"DOTS DOWN," for me!