Edirol Um-5 Options

[artisan]

Hi, i've purchased the edirol um-5 where i am now having some issues with the mic. i've got a behringer b1 condenser mic which only seems to play back in 1 channel. when i switch to mono i can hear from both speakers.

In stereo however, it goes back to just one channel. meaning left or right only. surely there has to be a way of getting it to work in both channels with stereo?

Thanks