10+ seconds screen sharing lag Adobe Connect 7.5 + Windows 8(.1)

Hello,

my company runs a Adobe 7.5 Server and is generally very happy with it bandwidth- and performancewise. But when a Windows 8, 8.1 Client is sharing his screen, the other participants are experiencing a severe delay / lag of appr. 10 seconds between the voice and the image from the screen sharing, which makes it really difficult to follow what the presenter is talking about. Of course this problem is getting bigger and bigger over time, because there are less and less windows 7 clients on which Connect 7.5 works perfectly fine.

We have tested the newer versions from 8 through 9.3 but we have experienced an increase in overall hardware usage and bandwidth compared to 7.5.

Is this a known issue and is there maybe a simple solution?

Thanks in advance,

Jan