What's wrong with my voice memo's on my iPod touch?

I have a second generation iPod touch. A few months ago I bought ear buds with a mic on them so I could record voice memo's. For months it's been working fine, but all of the sudden, whenever I record a new voice memo it won't playback. Even when I hit play, it remains at 00:00. So I tried to transfer them onto iTunes, because that's always worked. However, now iTunes doesn't ask me if I want to transfer voice memo's. When I unplug my iPod from the computer, the voice memo's are gone. It's not that the mic's broken either, because whenever I speak into it, the loudness meter on the voice memo app goes up and down. So it picks up the sounds. Is this a software issue?