Hi, reasonably simple question which requires a simple answer...i hope.

I am running an SM58 into a MOTU Ultralite which is connected by firewire to my G4. I am recording spoken vocals into bias peak and only require a dry signal as all the effects will be applied after recording.

My problem is that the levels i am getting are very low, even with the trim on the channel set at +24dB it barely tickles the signal meter. I know i don't need phantom power on the channel since it's a dynamic mic. Apparently the pad switch on the MOTU can add up to an extra 36dB to the signal but this isn't having any effect.

At the moment i have the Shure connected via TRS into the combo jack input but would the lower impedance of an XLR connector make any difference?

Do i need to pay close attention to the bit depth, sampling rate and clock source settings? What about balanced/unbalanced (clear that up?) there is only one insulating ring on the TRS connector so does that mean it is a mono jack. is this XLR to TRS cable even a suitable microphone cable...

I'm sure there are some obvious solutions but any help will be greatly appreciated

thanks in advance
tim