Hi Joe,
I wouldn't recommend using
ASIO4ALL as a fix for this, it is a generic ASIO 'wrapper' and is not optimised for our products. I would recommend uninstalling that to be sure that it doesn't give us any driver clashes at a later date.
Often, if a recorded signal is only playing back on one side, it means that it has been recorded to a stereo channel as opposed to a mono channel.
I've not used Windows Movie Maker, but check whether you're creating a mono or stereo channel when recording your bass.
The samplerate (44.1khz etc) will not have an effect on which side your audio is coming out of.
How do you have your speakers connected to your Scarlett, via the outputs on the rear of the SCarletts? If you play music through Spotify/Youtube etc, do you hear audio through both speakers?
Let me know how you get on.
Simon // Focusrite Technical Support