Share Content slow - Group Series 500

Dear colleagues,

I have a Group Series 500 integrated with S4B, when I do a point-to-point from my Skype's user with the Skype's user of the GP500 to share content (my desktop), the GP show the content sharing very slow, frame by frame ... but if I share my video then works fine.

I tested it with three different Trios and worked very fine the both scenario, sharing content desktop or sharing content video... just with GP500 I face this problem.

Do you have any idea about what can be?

Thanks,

Renan