A. Are the tracks panned .. RB imports files as centered if you iported to mono tracks. Stereo tracks should import to stereo (if imported to a stereo track).

B. check the mixer window, as there is a MONO button at the bottom of it that may have become enabled.

c. Check you drivers in Options-Prefs-Audio tab-drivers button to make sure you are using the drivers you think you are.

I do not work here, but the benefits are still awesome
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