Pop/maxed-meters/no-sound problem - video example

Here's a video of the pop/maxed-meters/no-sound problem. In this case it gets triggered by (of all things) checking aud.ini through the properties dialog. Normally just hitting spacebar is enough. Note the maxed meters on the Master and vox reverb buses, the maxed-out spectrum in SPAN (which is on the Master bus) and the weird RMS and peak values in SPAN (1.$). Hitting spacebar multiple times doesn't fix the problem but does eventually stop the vox reverb bus meters from being maxed. Stopping and starting the audio engine makes no difference. Turning all FX off then on again does fix the problem.
 
It's probably better to download the video (7.3MB) and play with your favorite video software. The video is a bit blurry played directly from dropbox.
 
Cheers, Peter.
 
p.s. There's no audio to this video - couldn't figure out how to do it - maybe it's not possible with ASIO drivers. When the meters max out, and whenever the transport or audio engine is restarted, there is a loud click but no other sound. Normal sound resumes after turning all FX off then on.
 

Well, I'll be damned! I disabled the 64 bit engine in Preferences -> Driver settings, an dmy problems have gone!
Granted, my problems only showed when opening a project, with buffers set too low - but the "problem" files have some VST3 plugs, and I had the 64 bit engine enabled.
 
Turning off all FX also solved the problem, so I knew that my problem is related to the others...