I had a lot of tries with Linux, Sparkphone and Java Sound this night. And now it works Are you interested of details? Or you’ve resolved this issue?
As for now, it still looks like a hack (patch from here http://www.igniterealtime.org/issues/browse/SPARK-625 helped too, but it’s hack), but it works and that mean you can create a good solution.
Btw, why Linux version doesn’t have a volume and record levels tuning as Windows version has? Or it’s because Windows version uses DirectSound?
p.s. May be only the patch is needed to work, i’m not sure for now. I’ve done a lot of rebuilding of JMF with jmfcustomizer, may be this helped too.