Optical burn-in?

Probably the daftest question of this year but I'm no expert so....
Does a toslink optical cable take time to burn in?
I know it's only carrying a laser signal.
I've done a search and haven't seen this thread before,I just changed to a Van Der Hul Optocoupler which seems more detailed but the bass seems to have faded into the background which in my limited experience sometimes is exactly what happens when either cables or components are brand new.
I'd be grateful for any experiences or theories but please let's not get dragged into another "burn-in" debate.
Thanks as always..

Ben