I bought a Jammate Hipster but it doesn't seem to work. After placing a (brand new) set of AAA Alkaline LR03 batteries, only the battery indicator lights (constantly). Whatever I do, nothing else happens. None of the indicator lights burn, no sound. This is already the second one I have; I returned the first one to my dealer with the same complaints. Now I'm wondering whether I do something wrong. Can you please help me with this problem?  

UPDATE: I resolved this problem. The Hipster only works when a guitar is connected. However, I used a stereo Guitar cable. The Hipster only works when using a mono cable! Problem solved!