Spout - Flickering

I have tried to use spout in order to use a vvvv-beta-renderer output in resolume. It is generally working, but there is a problem:
There is a flickering (=white frames) occuring in my test patch. It happens quite irregularly, in sum about every 4-5 seconds. This is both true in resolume as well as in the spout monitor. I am using beta 42 64 bit.

Is this a known problem? I am not sure, if I have the ideal settings in the renderer - I have copied them from the spout help patch. What I have also noticed, is that syphon stops showing the image when I hide the renderer in vvvv (alt+3) - but I guess this is normal behavior.

Thanks a lot in advance, any help much appreciated!

spout example patch 1.zip (2.1 KB)