I have a fishman sound hole pickup on my guitar, I found that the signal level is too low for the backtrack to activate recording. When using my Ibanez which has a preamp, the backtrack works fine, I am ordering a LR Baggs Gigpro Universal Preamp for Acoustic Guitar which should solve my low signal level.

The fishman has a very low signal level, (even though it uses a button battery) when I play through my amp, I have to turn the gain all the way up in order to obtain sufficent volume levels, but with my guitars that have preamps built in, I don't have this problem and my gain doesn't have to be turned all the way up for these guitars.

Maybe in the future Line 6 could modify the Backtrack to work off of lower signal levels, the Backtrack is a great concept for guitar player and is a indespensable tool once added to your collection.