Audacity 1.3.12 and Audacity 1.3.13 svn
Linux (Ubuntu 9.04)
Easiest way to reproduce this problem is with a "naughty" Nyquist
1) Open Audacity
2) Import or generate some audio
3) From the Nyquist prompt run (lowpass8 s <frequency>) where
<frequency> is greater than half the sample rate.
Not surprisingly this produces rubbish (all sample values set to -1.0)
4) Undo everything (or "File menu > New", or delete the track)
5) "Generate menu > tone" does not work. (all
sample values set to -1.0)
This problem persists until Audacity is restarted.
This does not occur with Audacity 1.3.11