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When I listen to music....which isn't often...(well get to that in a bit), I use a cable connection (headphone > Aux-In) on my $30 WalMart AM/FM in-dash radio....no cassette, no CD.....just AM/FM.
I set my X5/400 volume to medium and the volume control on the radio to whatever is necessary to hear it.......sounds fine to me......
........Of course, I'm deaf in one ear (so
STEREO really means nothing to me), going so in the other
my '93 (230k mile) Nissan pick-up has no AC so the windows are always down
and my speakers are pretty much like Dixie Cups with refrigerator magnets in 'em.
.......but the sound quality and volume is
great by my standards.

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