Erratic USB behavior with keyboard

Lately my keyboard is acting strange when I insert my iPod. The iPod gets connected, then disconnects, and connects again. This happens about three times and a warning about Low USB power appears on screen. These days I insert the iPod in the USB hub and there are no problems, but accidentally I put it in the keyboard and got reminded again with this issue.
My iMac is about 1.5 years old, so it might be some sort wear, but other things (like my external Audio/MIDI device) simply works on them. Anyone familiar with this behavior? Time to get a new keyboard?

 

Weird. I always put it in the keyboard's USB without any problem. Just lately (the last three months or so) I got these connect/disconnect goings-on. As I said I put it in the hub and forgot about it, until a few days ago when I accidentally put it in the keyboard as it is way more handy than the hub.