Windows Vista and Tascam US-122mkII dont work well together as i have a laptop running Vista and Le5 with a US-122mkII.
Problems i have had are not recording vocals this was due to having a mic plugged into the left input and also having something plugged into the left line input at the same time.
Line input overides mic input.
Also for some reason Le5 would switch off inputs so none connected.
Also unless your mic is stereo it will only record on the left or right depending which input you plugged it into.
If your mic is mono then you need to create a mono track.
When recording vocals it is quite normal to have many tracks 10 or 20 if needed. Then keep the best bits out of each take and mute the rest.
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