audacity is a poor choice of daw first off... it doesn't support ASIO natively and you really need good ASIO support for low latency recording...

try reaper http://reaper.fm it's free to try and only 60$ works on an honor system so it will continue to work whether you pay or not....

anyway just a friendly suggestion for a big boost in your abilities....

there are many other recording programs most are alot of money... i figured you probably chose audacity because it was free... anyway... i personally use ableton.

the levels are low on purpose when you are only hearing the dry track... this gives you lots of headroom when adding the amp models and effects....

if it was already loud to begin with, you would start clipping your audio before you could really drive your tones... especially if you are after high gain kind of tones.

i do suspect the only one channel thing could be your selected input for recording....

but your choices won't be guaranteed to be proper until you get a recording software that natively supports ASIO drivers... specifically the line6 ASIO drivers and not ASIO4ALL or any other workaround type driver.