Actually, I was mistaken in that defect ID. Sorry about that! The correct one is CSCtf90785. There is no direct workaround via Visual Voicemail unfortunately; i.e. the playback settings can only be saved when you use PCA/Unity Assistant, the Telephony User Interface, and/or admin web pages.
Currently I see the defect is being addressed in Unity Connection 8.5. If there is an urgent need for it to be addressed earlier, I'd suggest opening up a TAC case as they would be able to see if there are any plans to integrate it into another release or something like that.
These are the paths to get to each CCX logs through CLI. They may be helpful if you are having issues accessing RTMT or downloading logs through it.
If you want to download them you have to prefix "file get " and you can add one of the options (re...