We have been running an Onkyo TX-SR605 since it was released (so circa 2007/2008 or so) and it has powered two different systems, first in an apartment we had and then in a house we moved into. It actually does everything we need, save for the height formats of course (Dolby Atmos/DTS:X), as it decodes Dolby TrueHD and DTS-HD Master Audio, along with all legacy flavors of the codecs (this is important to us because 99-percent of our disc watching comes off of DVDs or regular Blu-rays that boast either a Dolby Digital, DTS, Dolby TrueHD or DTS-HD MA soundtrack).
Originally, when we were set up for 1080p, we had our Oppo Blu-ray player at the time going through the 605, sending video off to our Sony SXRD rear projection display. but since getting a new 4K TV, we were forced to use our 4K players' (we had both a Cambridge Audio CXUHD and Panasonic UB9000 for disc playback duties; the 9000 is being used exclusively now) dual HDMI outputs so the old audio codecs could go direct to our old Onkyo amp and the 4K video could go direct to our display.
Now, in order to check my AVR settings from time to time on our 4K Samsung, I had to perform a workaround -- because, again, my old Onkyo can't pass 4K video -- by sending the HDMI output of the receiver into an empty HDMI socket on the TV JUST to check the settings menu of the receiver. I have noticed, however, over the past few months, the video output from the 605 has been degrading to the point that what started out as weird green "flashing lines" going across the screen are now very strange graphic distortions that sometimes cover the words on the setup menu selections. Just the other night, when I was checking receiver settings, the output acted up again, where the green flashing lines turned into weird distorted graphics, and then I even experienced freezes where the receiver's remote wouldn't let me scroll back a page or get to another section of the setup. I had to shut the receiver off three or four times during this process to be able to get back to the menu I was on because the whole thing froze.
Initially, I thought this may have been the HDMI cable I was using between the receiver and TV going bad, but then I thought....a bad HDMI cable wouldn't cause the setup menu to freeze or not allow me to go back to a previous page via the RETURN button on the remote. Then I thought maybe this has something to do with the fact that I connected the receiver's HDMI out to my Samsung display's HDMI port with the ARC -- like maybe it's not "compatible" with that socket...but then I figured that really shouldn't be...
Does what I am describing sound like the HDMI output of the Onkyo is finally failing after well over a decade of heavy use? As I said, I'm only using the receiver's output to check the settings from time to time, but I really do need to have a working HDMI out to do this (I don't want to rely on the AVR's front panel); does it seem like these distortions and freezes I'm talking about are indicating the HDMI out chip is just about done?
If this is the case, it's probably not worth trying to fix, is it? While the receiver is doing everything we need it to do, if it did come down to needing to replace it because of this problem, we'd have to just get a new one (at that point we'd obviously be upgrading to an Atmos and X-capable model so we're be future-proofed).
If this is something that would be better visualized through pictures, let me know and I'll snap images of what I'm seeing in the setup menu.