I recently picked up an 'almost new' Boss Micro BR. I tried it out to test it having only skimmed the manual. I turned on a 'rhythm' drum track and used the onboard mic. To my ears through the phones it sounded fine and I was impressed. I tried the connection to my Win PC and downloaded the 'song'. ... no drum track ... just my voice. I looked at the section in the manual about the rhythms, and I can play them back, but I'm not getting them into the 'song'. What have I overlooked? and THANKS