[alcook]

Thought I'd share a few weeks of pain wondering why certain burned CD's of MP3 tracks and audio books simply failed to play on my 55 plate 335d.

It took some searching to rectify and my apologies for those who already know the solution, but I'm hoping to reach those who may have simply given up. Of course some models may differ, but mine certainly is one temperamental bugger.

I was going to post here as a last resort, but worked it in the end..

Problem
A burned copy of some songs / audio in MP3 format failed to play. The track list would come up in the iDrive, but the player would not play it and simply skipped to the next track and the next etc.

The CD's and tracks would work in other CD players, PC's and laptops. But not my car.

As it's not a 'proper' CD, BMW won't support 'copies'.

I Discounted

The CD player itself as it played other MP3's, songs, books etc with no problems.
Burn speed, disk make and type. I tried multiple disks, types and burn speeds. The same songs wouldn't work regardless.

I copied the MP3 data from one format to another and back again and even re encoded in MP3. No joy.

In the end I settled on a CD-RW from verbatim burning at 10x.

Resolution

MP3's need to be sampled at a Constant Bit Rate (CBR) of 44.1k (44100) to be playable. Anything either side will simply be skipped as unrecognisable.

My CD / Collection burning is done at 44.1k with various bit rates dependent upon their source and fidelity. As some of my audio books and music had been sampled at different rates at source and burned from that copy, this caused the hidden problem as Windows doesn't show all that technical data.

Bit rates figures do not affected to problem, so use 320 if you wish or 48 for Audio books etc.

I haven't tried Variable Bit Rate etc, but I'm aware it prefers CBR.

That's it really. Easy as that.

Simply use a MP3 editing tool to check that the Sample rate is 44.1k and use the same tool to change it if not.

I'm off for a celebratory pint.