Originally Posted by Hyrax
Try changing your output resolutions and see if any of the options work for you. You can have both the Component and HDMI connected at the same time and may be able to switch inputs on the fly (depending on your TV/Projector ... it may not instigate a HDMI hand-shake after switching inputs).
Sorry, I neglected to mention that this was already tried the same day the problem had initially occurred.
Had managed to resuscitate the port again for a mere 5 minutes before audio/video went blank with the dreaded "No Signal" error.
It will still display the welcome screen at boot up. The HDMI port itself is tight and mechanically sound...I just can't isolate the problem.
None of the usual TiVo repair services have any clue how to resolve this and suggest exchanging for another unit. It's thought by some to be a partial failure of the BCM7401 CPU itself. That could very well be the case since the chip's datasheet specifies that the HDMI controller is in fact integrated.
However, it could very likely be something easily overlooked and simplistic such as a blown diode, open resistor, leaky capacitor or failed SMD transistor.
Considering pulling the mainboard soon to take a look-see. I have experience repairing advanced electronics. I'll cross check as many circuit traces as possible originating to the port, test probing every component as I go along. Just wish some solid repair documentation could be found for these units. When it comes to locating TiVo service manuals, it's a desert out there.