I found a site that has a couple of different Smooth Jazz channels.
Slacker.com
They have a SJ station that I think has a nice combo of vocals and instrumentals with actual jazz vocals and yes a few AC and UAC crossover tunes, and a non-vocal channel, though it plays a lot of covers, which is the death of the format, but at least you have options.
Slacker.com
They have a SJ station that I think has a nice combo of vocals and instrumentals with actual jazz vocals and yes a few AC and UAC crossover tunes, and a non-vocal channel, though it plays a lot of covers, which is the death of the format, but at least you have options.