((Hope this is posted in the right place, it's kind of an odd subject))

Hello Volvo Forum members and thanks for any help you can offer.

I have four cars, each equipped with a head unit that reads music from a rear USB drive. I am looking to purchase replacements for two of these car stereos.

My question is this...

How do we determine HOW MANY songs a head unit will read and play via the USB port?

Some head units read 100 songs, others read 300 songs.

Is there some particular spec I'm looking for? Memory count? Obviously I am looking for a 300 count or greater. Typically a 16 gig thumb drive works best here, more than that and the read time is too long.

Pioneer always worked well for this, but since they rolled out Mixtrax I will no longer buy their products and need to replace the one I bought with this dorky program built into it.

I've run tons of Google searches, e-mailed car stereo manufacturers ... even asked sales reps. No answers. Anybody know anything about this?

Thanks very much
(clanton65)