Just an update to the problem I've been having. I turned on my car and the audio was not working, so I drove directly to the dealership. Service Rep acknowledged (finally!) the problem and got the tech to come out and also acknowledge the problem. I also showed them the TSB and the version of the software my car had. It seems that their computers incorrectly had it stated that the update had already been applied. Regardless, they ran the update this morning, so we'll see if it actually fixes my problem. According to the tech, Hyundai stated that my problem (audio issues) should be fixed by the update, but we'll see.
On the way to the dealership, I also had a second issue - halfway there (about a 30 minute drive), the DIS restarted (rebooted), showing the accept screen again. It happened a second time in front of the tech. I don't know if this is all centered around the same issue, but since it's the DIS "computer", and an update has just been applied, maybe it will go away.
While I haven't had much time to notice improvements, I did find out that it fixed another issue with the voice recognition. My brother's name is Jesse (pronounced Jess-E, not just Jess) and I had two numbers in the phone book - Jesse Work and Jesse Cell. If I said "Call Jesse Work", it would call Jesse Cell. If I said "Call Jess Work", it would call the correct number. When the DIS voice confirms the command, it pronounces Jesse as Jess and still does but now it correctly understands "Call Jesse Work". Perhaps the algorithms have been tweaked?
Regardless, outside of all the data entry, I'm happy at least that the voice recognition works a little better. Whether or not my other issues are fixed is unknown until it happens again - or never happens again.
BTW - By the time the tech drove the car around to run the update, the sound started working again. Luckily it stayed broken until he came out, otherwise they would have still thought me crazy!