Ah yes, this is a bit misleading. I mean monophonic in contrary to polyphonic (FLAC and all other codecs have to work with fully mixed and mastered songs, which isn't the case when just using samples).

Yes of course. They are even embedded in a HISE Playe library.

You could also skip the namespace. and write the variable name without prefix. This will work even if there are global variables with the same name.