Got a problem with the HDMI output!
So it's the lead-up to Christmas and I'm trying to get the lounge-room installation finished before the extended family descends on us next week. So last night I moved my H77N-WIFI box out there and slotted it in below the TV. Took out a 19" LCD as well connected to the DVI, and connected the TV (a Hitachi 720p plasma) to the bottom HDMI port. The TV's VGA input is currently being fed by a Mac mini.
Powered it up: all fine. Hmmmm: this room's very quiet. Will have to do something about slowing that fan down a bit, and maybe I
do want an SSD for the lack of noise.... Anyway, the system recognised the TV and I had a dual-screen setup running. The DVI LCD was the primary display (with menubar/etc) and the TV was secondary.
The HDMI defaulted to 1080i, but I switched that to 720p no problems (that's 1280x720x32@60). At both resolutions the TV was clipping the edges of the image, but in this old unit I could not find any setting for turning overscan off.
But in the Displays Preferences I could move the Underscan slider to about the half-way mark and see the edges again. I know this isn't optimal (we're wasting pixels by ignoring the bits that the TV will throw away) but it worked fine. All good so far.
Now to disconnect the DVI and use only the HDMI. Unplug, and it looks great. But reboot, and we're screwed.
Upon booting, the screen is at 720p but the edges (e.g. the dock, the menubar) are clipped. Obviously there's no underscan happening. Go to Display Preferences and the slider's in the same position, but I move it and there's no effect. Until I move it to 0, at which point the screen goes crazy, with portions of the screen interlaced throughout each other. Move the slider a fraction off 0, and it comes back to normal (but still with the edges clipped). WTF?
If I re-select 1080i it doesn't work like before: it's squashed horizontally (circles become ovals). Same goes for 480 resolutions, etc. 720p is OK, but with overscan. Argh!
I'm able to use Screen Sharing from a laptop to see and control the machine remotely even when the display is garbled (or I can't see the menubar, etc). And I can re-connect the DVI LCD for now, so all is not lost. But right now I'm scratching my head!
Does anyone have any suggestions? If I could disable overscan in the TV my problems might be solved, but seriously I can't find it. And the TV's menus aren't
that complex.