This is the error I get when I start LMMS from the command-line. (LMMS from the GeekOS repository)
guus@localhost:~> lmms
Lv2 plugin SUMMARY: 202 of 337 loaded in 2466 msecs.
For details about not loaded plugins, please set
environment variable "LMMS_LV2_DEBUG" to nonempty.
Lv2 Plugins blacklisted: 10 of 337
If you want to ignore the blacklist (dangerous!), please set
environment variable "LMMS_IGNORE_BLACKLIST" to nonempty.
"Cannot load library /usr/lib64/ladspa/caps.so: (/usr/lib64/ladspa/caps.so: undefined symbol: _ZN3DSP10Polynomial5one53Ef)"
"Cannot load library /usr/lib64/ladspa/gong_1424.so: (/usr/lib64/ladspa/gong_1424.so: undefined symbol: waveguide_nl_process)"
Cannot load library /usr/lib64/lmms/libvsteffect.so: (/lib64/libQt5Widgets.so.5: version `Qt_5.15.8_PRIVATE_API' not found (required by /usr/lib64/lmms/libvstbase.so))
Cannot load library /usr/lib64/lmms/libvestige.so: (/lib64/libQt5Widgets.so.5: version `Qt_5.15.8_PRIVATE_API' not found (required by /usr/lib64/lmms/libvstbase.so))
Cannot load library /usr/lib64/lmms/libmalletsstk.so: (libstk-4.6.2: kan gedeeld objectbestand niet openen: Bestand of map bestaat niet)
Cannot load library /usr/lib64/lmms/libvstbase.so: (/lib64/libQt5Widgets.so.5: version `Qt_5.15.8_PRIVATE_API' not found (required by /usr/lib64/lmms/libvstbase.so))
Seems to be an Qt issue ?
LMMS still works but it cant find Vestige anymore.
Not sure if the ladspa part is related, the important part for me is about the libvst errors.