Do all CD players benefit from burn in?

Is it a general rule to burn them in for a few hundred hours? I have found that the handful of CD players (or DAC/Transport combos) I've owned seem to get better, especially in the frequency extremes (more control, less boom or sizzle).
I feel that you are correct in burning a cd player in for a couple of hundred hours.
There are a lot of capacitors to burn in.
There's OPAmps to burn in also.
I have usually seen the figure of 50 hours quoted for CD players, which was about right for mine. Things like tubes will take a little longer, more like the 200 hour figure.
Mark Gurvey of TEAC & Esoteric told me that the DACs take about 400 hours to fully settle in. I've also heard that figure bandied about on other forums and posts. I have no reason to doubt it.
'settle in', give me a break. the high end business model is built on that type of nonsense.
Considering all the wire,capacitors,resistors, transitors,tubes,transformers(more wire yet again!)etc. It`s only logical that all of these components need time to form and become seasoned. At lease in my experiences every component has improved with the additional hours(some subtle and others dramatically).Oops! almost forgot, YMMV.
Like Buconero117, for the longest time I thought component burn-in was a load B.S . It just sounded like a load of crap and that it was really just a period of time for the listener to adjustment to the new sound .I now know differently.

Edgy and bright will still be edgy and bright after 200 hrs. The listener adjustment wont overcome that.
Burn in will.
Having just finished my system (added cables) I wondered this. I use my wife as a guinea pig as she has better hearing and no idea what stuff costs. We both have found that any a/b comparisons suffer greatly after a few days (maybe less) and we are unable to tell any difference. Mind this is differences in specific samples we selected to test. I'm gonna stay out of this fight but I'm curious if folks do anything different for long term comparos than they would short?
Short answer is yes, I just reached about 500hrs on an Oppo 95 and witnessed it first hand!
During and after burn in, I find it helpful to leave the players power switch on.
sometimes a piece of equipment sounds worse over time, i.e., it gets bright and aanalytical and it sounds better , out of the box than after 500 hours.
Buconero, I had my SACD player upgraded and when I played it It sounded dull and dark. After a 100 hours it opened up. The new tubes had to burn in as well. Mike
These changes, if they exist, occur so gradually it's hard for me to tell if they're real.
I don't believe my CD player, which surely has more than 500 hours on it by now, sounds any better than we I picked it up. Same with my tube amp.