Explanation done... I'll say again what is said in the Wiki. It is easy to test.
UNINSTALL ESET completely, reboot, and then test it again.
If the leak goes away, well, then, you have your cause. You can contact them and tell them that their application is breaking JRiver Media Center 20, and to please fix it, and/or you can add exceptions to protect the JRiver processes and storage locations when you reinstall it.
If it does NOT go away, then we know, beyond all doubt, that it is UNRELATED to AV and can move forward to investigate the cause.
No one is suggesting you run unprotected. We're suggesting that the only way to be absolutely sure the AV application isn't causing issues, because these kinds of issues are OFTEN AV behavior related, is to remove it and test. There's no way this should take a huge amount of time. I'd be willing to bet I spent more time writing these two posts than it would take to do it. Even with SEP (which is very annoying to remove and reinstall), it would take me no more than 20 minutes to uninstall it, test, and reinstall it after.