2003 Trailblazer factory radio + cd + cass = mp3 play?

Mp3 is a type of encoding, it has nothing to do with speed. If your factory unit is not an mp3 unit then it cannot play mp3 encoded discs (and if the unit plays mp3, it will say so in the manual). The rate of encoding means nothing when you play it back, it only means that the disc was "written" at that speed (which translates into how much time it took to write the disc).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% There are two classes of pedestrians in these days of reckless motor traffic - the quick and the dead. ~ Lord Dewar 1933 ~

Climbing into a hot car is like buckling on a pistol. It is the great equalizer. ~ Henry G. Felsen 1964 ~

You left a few things off your useless resume'. You're an anal secretion, and not really qualified to do whatever it is you do. As for me, I'm a retired technician, a veteran and I've seen more shit than you will probably ever see. The next time you crap in you diaper, change it yourself - s*****ad.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% There are two classes of pedestrians in these days of reckless motor traffic - the quick and the dead. ~ Lord Dewar 1933 ~

Climbing into a hot car is like buckling on a pistol. It is the great equalizer. ~ Henry G. Felsen 1964 ~

...The rate of encoding means nothing when you play it back, it only means that the disc was "written" at that speed (which translates into how much time it took to write the disc)....

Sorry friend,

A compressed audio format that is popular for downloading across the internet and for use with memory-based audio players. Files may be recorded on CD-R or CD-RW media for playback in compatible DVD players, audio CD players, and CD-ROM drives. Files are usually named as "*.mp3". Sound quality varies as a function of the recording/encoding bit rate. In our opinion, anything recorded with less than 128 kbps data rate will sound degraded.

The recording bit rate ( or in the music world sampleing rate) has to do with the way the sound is compressed and played back. with a rate of 128 the player must convert the digital information back into analog for the sound to be sent to the speaker. Many players have the ability to convert all of the standard rates, some do not.

You may want to check you facts before you open your mouth and make yourself look like a fool.....

What may be going on is that the player is trying to "play" the Mp3 as a cda (cd audio, the native format for commerical CD'S). This I have seen happen more than once..........

if this is the case you can add a rf modulated cd/mp3 player or a Mp3 player harddrive system to your current system....

I have an XM unit with a behind the dash RF modulator but I was really hoping the stock deck had the unadvertised ability to decode MP3 since it didn't just spit the disc but rather showed it was playing tracks. I have seen others require a specific recorded bit rate that would play the track but not be able to decode the audio. I still haven't tried other rates besides what I thought might be fairly standard at a fixed rate of 128. However it may just be the fact that it will not play MP3 even though the same deck in newer models did.