Anyone know much about these things?

When I turn on my Telstar Arcade, the picture does not come up. It DOES send a video feed, because channel 3 goes from snow to more of a grey and black static-y screen (and yes, the Telstar IS set to channel 3 and I have tried channel 4 too--same deal.) Sometimes I can even see the faint silhouette of the graphics. And if I twist the system just right, a complete and perfect video feed will flash on the TV for a split second before slipping back into the grey and black mess.

The system still produces audio just fine.

Thanks for the tips, if you've got them!