My prior TV had analog outputs for the sound. This enabled me to route the TV signal into the Torii MK IV. My new TV unfortunately has only an optical digital output. So I resorted to the RCA outputs on the cable box. This allows me to only route the signal from the cable provider, not when watching Netflix prone of the other streaming services. It also brought with it a quirk. There is a delay between the TV signal and the audio signal when coming about of the cable box, which is more noticeable when watching news programming.

Is there a small D/A converter I could use to connect the digital optical output of the TV and run the analog signal to my MK IV?

Why didn't you go with the TV Optical output? I had the same problem, audio didn't match on new Sony Bravia, delay, also Netflix And HBO stopped sending signal through apple tv optical, so i got a new longer optical and ran from tv to dac. No delay, and it even runs sound to stereo through tv, as I use a digital antennae, plus audio for for all smart tv apps.

Sorry, I had too many New Years drinks, I see the issue is that you need a DAC.  There are Musical Fidelity VDac's on ebay for 41 dollars. They don't make them anymore, but it was a decent little dac. Has optical input.

My solution arrived this morning. I connected the cables and voila! No time delay between picture and sound. There is some digital glare. I will connect my ZStage between the components to see if it removes some of the glare.

I only have a 2.1 channel setup for both music and movies.  My McIntosh D100 DAC has multiple inputs including Optical and USB, etc., but it is hooked to a McIntosh C220 preamp and I would need to use 2 remotes when switching from digital music from my PC using USB to and cable TV via optical if I wanted to use my DAC.  1st I would have to use the D100 DAC remote to switch from USB PC to Optical (cable) and 2nd use the C220 Preamp remote to switch from PC to TV.  This is OK and works, but my girl is not too handy/technical when it comes to turning stuff on.  So instead of having the cable go into my DAC via optical, I bought a cheap RadioShack DAC and have the optical of my cable box go into the RCA DAC which goes directly into the Preamp, so there's no need for additional step of using the DAC's remote.

The sound is of the RadioShack DAC course not on the same level as the McIntosh DAC, but cable TV is really a low priority for us and we barely watch TV through the cable box at all.  We stream most everything these days and most cable TV channels also have websites that you can watch from.  So there is nothing really important to us as far as sound quality from the cable box.

Does that DAC have a volume control or does your TV remote still control the volume.  I thought about setting up a 2.1 setup using a Schiit pre-amp which has remote control.