mic-in on the JB3 sucks (very noisy)... the line-in is better as long as you've got enough gain to get decent levels (though I'm still on the lookout for a cheap AD20 or similar so I dont have to use it either)... You might need to put a preamp or a line-transformer in between the CSBs and the JB3. I recall finding a great web site where someone did some extensive testing of the mic-in vs line in... my own ears have told me this guy was right on when he recommended never using mic-in.