Sometimes it is just good to know that linux-life can be as easy as imagined, in this case by using SoX (Sound eXchange):

sox infile.flac outfile.flac repeat 32

this even works with different file formats like:

sox infile.flac outfile.mp3 repeat 32

would loop into a 128 kbps MP3

other bit rates can be set using the option:

-C|--compression FACTOR  Compression factor for output format

getting an 320 kbps MP3 would be obtained with this command:

sox infile.flac -C 320 outfile.mp3 repeat 32

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and finally a simple gapless playback from the command line with mpv:

mpv --loop-file infile.flac

or the same even simpler:

mpv --loop infile.flac