I have no idea what is wrong with them, all know is that they don't work. Could be a loose wire, could be a bad battery terminal – who knows! It might be an easy fix, or it might be hopeless. In any case, ALL 6 are being sold AS IS and FOR PARTS or REPAIR ONLY – NO RETURNS!
SONY M-750V
SONY M-555V
OLYMPUS Pearlcorder S911
OLYMPUS Pearlcorder S911
OLYMPUS Pearlcorder S911
PANASONIC RN-105D
Winning bidder to include US$9.00 domestic PRIORITY S&H (includes Delivery Confirmation & tracking); US$29.00 Canada; US$40.00 worldwide. Be sure to check out my store (White Dog Trading Post), as I am more than happy to combine multiple purchases. Thank you for your interest, and I look forward to doing business with you!