[Lex]

Quote:

Not necessarily true... in theory, anything with a capacitor in the signal path could benefit from burn-in. In practice however, I doubt your ears could tell the difference, or that an mp3 player would be revealing enough to even show a difference.

I seem to remember an electronic engineer friend telling me that caps do require burn-in but the process is complete about a nanosecond after first power-up.... 

 

[TCD1975]

Quote:

I seem to remember an electronic engineer friend telling me that caps do require burn-in but the process is complete about a nanosecond after first power-up.... 

 So in answer to the OP's question yes, you do need to burn your MP3 player in. For 1 nanosecond.