No audio when connected to ancient TV

I've got an ancient Sharp Aquos that has a single HDMI input which is likely a very early revision of HDMI. I also have an ancient AVR that has no HDMI inputs at all. I replaced a Premiere that I had connected to the TV with an HDMI cable and to the AVR with a digital optical audio cable with a mini. Since the mini doesn't have an optical audio out, I got a JTech HDMI audio extractor and connected the HDMI out of the mini to its HDMI in and its HDMI out to the TV. Then I connected the JTech's optical audio out to my AVR's optical audio in in the same manner as I had done with the Premiere. I ended up with picture but no sound. To verify the JTech wasn't the problem I took it to another TV with a working mini and tried the same sort of audio connection to that TV's AVR (which is quite a bit newer and does have HDMI inputs). That worked fine. So the JTech works, just not when used with the ancient TV and AVR. So I thought maybe the mini had a problem. So I moved my Roamio Pro to the old TV/AVR and this time I got audio but no video!



So I am thinking there's some kind of HDCP negotiation failure going on that is preventing the JTech from working with the old TV and AVR. Is that plausible?



Replacing the TV is not an option, but I thought maybe replacing the AVR with something more modern that does have HDMI inputs would solve the problem (as it would eliminate the need for the JTech altogether). I worry a bit that maybe it won't be able to pass the video along to the TV. Could that happen? It seems to work OK with the old Premiere. Is there a different level of HDMI/HDCP in the Premiere than in the mini that is more fussy somehow?



Thanks for any insights.

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bc