Can you force higher CRT refresh rates on TH2GO?

[Cygnus]

I'm using a dth2go on crt monitors.

Anyone aware or have experience of trying to force a higher refresh rate?
Maybe some tweak or setting that is 'unofficial' or 'unsupported'?

I remember my parhelia used to be able to do 3 x 1152x864 at 85hz...