[AMSAT-BB] External display for IC9700

Hi. I've recently started using N1MM together with a PC monitor, to enable a large external display for the 9700. Operating on a single band it's great, I can click on the waterfall and the radio moves to that QSO, you can even fine tune with the mouse wheel. But as soonas I change to satellite mode, the link between the computer and radio becomes unstable and fails after 5 seconds or so.

Is this a known problem, or have I missed a setting or two in the radio set up menu? Thanks David  G0MRF