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I'm pretty sure that this is a driver/XP problem and not a Reaper bug. Reaper requests one sample rate from the driver and other applications can't reset this for some reason or something along these lines. The Echo driver changelog recommends setting all applications to the same sample rate:
http://www.echoaudio.com/downloadfil...C%20readme.rtf
- How to set Reaper to request a specific sample rate from the driver:
- Another easy fix would be using the onboard sound chip for Windows sound/other applications and so on.