[Coco] Monitor proboems

[Bill Gordon]

Does anyone else have a Roy Justice monitor converter?
I've finally been able to get it set up, and NitrOS-9 is IMPOSSIBLE  with
the converter and monitor.
The screen does fine while NitrOS-9 is booting, right up until I get the
{Term|02}/DD: prompt. After that, it flashes a few times, then comes back
on, but continues to flash-mostly staying black. In RSDos, everything is
perfect. It comes up and doesn't falter a bit.
I don't know if it's the converter or the monitor. I've tried it with other
monitors and another Coco3, and it does the same thing.
(Ideas?)
Thanks