Focusrite Scarlett 2i2
Sample Rate: 44100, 16bit (48000, 32 no good either)
Record new mono track perfectly
Open second mono track to record from same input and I get the Invalid sample rate error message.
Update: As a grope, changed audio settings to use either MME, or DirectSound and no error message. So, the error only occurs with WASAPI. Hope this helps.