You don't have safestrap? It works quite well for the locked 4.2.2 Verizon versions.I just got an S4 last week after my wife took over my rooted & custom rom S3. I'm stuck with the MF3 version and have it rooted, but other than doing things like using Titanium Backup, what else is the rooting good for since custom roms are still out of the question.
You can try Adapt Sound in Settings>My device>Sound.Perhaps I missed a certain setting. Will try to dig deeper.