[Uatschitchun]

I managed to reproduce the memory leak. So it is not just RPi or LE, or at least some elements aren't.

Ah.. nice
That will make fixing easier!

Implication is that it is the memory used within overlapping CMusicDatabase::GetSongsFullByWhere() calls that isn't being cleared fully, rather than JSON output. Next is to see if SQLite will do it too.

That's what I found with testing. Must be something happening when overlapping queries apper.

the "Schwuppdizität" will surely improve

Is that German for memory leak?
Google gave me "sloppiness" as a translation

lol, no, it's an invented word from a german pc magazine coming from "Schwuppdiwupp" (presto, blink of the eye, quickly) and is meant as a felt speed of a computer. Some kind of reactiveness, responsivity