Problems with waterfallsink2

Hi,

when I start the audio_fft.py example in waterfall mode (option -W) I
get only a frozen GUI.
An empty time vs. frequency display is shown. The buttons, slider and
menu don’t react.

In scope or fft mode it works as expected.

I’m using the precompiled gnuradio 3.2.2 package on ubuntu 10.10.

I’d be thankful for any ideas.

Regards,
Curd