That would seem to be a new problem. If others had experience it, I'm sure it would have been reported.
Someone is sure to ask you what version of software you're running. If it is old, then it would be worth updating to see if the problem goes away.
Here is some well-intentioned advice, which you are free to ignore ;o)
Don't use the analog recording feature of the B2. Do your recording on your computer using an appropriate program that was designed for that, such as Audacity (which is free, and very good). Then you can trim the recording into
separate tracks and Import them onto the B2.