Solved the problem with the rare stocking. Edit in the .app folder in Contents/Resources the files dboxcommander and dboxcommaderrec and insert the following: --file-caching 5000
It should look like this:
./ggrab -q -host $dboxip -port 31338 -p $vpid $apid $apid2 $apid3 $apid4 $apid5 -o - | "$vlcpfad" --file-caching 5000 /dev/stdin -v 0 >> /dev/null 2>&1
and in the dboxcommaderrec file also insert --file-caching 5000 in the same position.
The 5000 is the cache in ms....so you can reduce it until it starts stocking again to minimize the delay in playback