As you know, I owned a 2003 ES300 with the Mark Levinson sound system and it would NOT read a disc with MP3 recorded content! In fact I looked at the '03 Owners Manual and it didn't mention the ability to play this type of disc at all!
My ES350 Owners Manual on the other hand has many pages devoted to the CD player when playing MP3 discs. When I play an MP3 disc in my '07 I get all the information on the NAV screen, such as, name of the tune, performer, running time, folder allocation, etc. One of the MP3 discs that I recorded had about 168 tracks, which would actually play for about 8 hours.
I also decided to call the audio maven from Bay Ridge Lexus to ask him about playing MP3's on an '03 ES300, and his answer was unequivically NO. He furthermore told me, like I said in a former post that the circuitry and player was not designed to play MP3's!
So, I therefore stick to what I said in my above post. <_<
P.S. The compression scheme circuitry for MP3's is NOT included in the the Mark Levinson sound system in 2003 ES's.........so I don't know what you're talking about??