Channel keys get saved in a very wrong way

[PotcFdk]

We're experiencing a problem with ZNC 1.6.0 connected to Unreal 3.2.10.4.
After a while (not sure when it actually happens, I haven't looked into that yet), all saved channel keys each get replaced by an amalgamation of all keys, which looks like this in the web panel:

or like this, in the config file:

I noticed, that apparently there been multiple channel key related issues in the past, some of which still seem to be unresolved (?). Has this exact problem been reported before, or is it related to any unresolved issues?