Sound Tweak Rpi4

[DRONE7]

Are you sure it's caching NAS files? The TODO comment in the code and this issue suggest that only local files (USB, SDCard) are handled. https://github.com/MusicPlayerDaemon/MPD/issues/597

Here's some other items relating to input cache.
https://github.com/MusicPlayerDaemon/MPD/issues/603
https://github.com/MusicPlayerDaemon/MPD/pull/696

All I have connected is a NAS and yes it is caching from there..

I have a couple of cd rips from cd reissues of original LP's. These are each 2 tracks in length corresponding to Side A and SideB.
I see the memory usage jump accordingly as each of these is cached prior to mpd playing them.

Caching seems to be on a track by track basis so one of the interesting observations with these large tracks is that after they are loaded  the NAS hard drive spins down. (after it's selected park time set in OMV) whereas ordinary tracks are cached and short enough that the NAS drive continues to spin.

I am using Philrandal's suggestion of 1024 MB and having hit that the cache has now been managed down. Top and System info report total memory usage so depending on what MoOde processes are happening the cache/memory use can appear to grow beyond 1GB before management kicks in. Mine hit 1.12GB before it dropped back.