[ginko]

Did you add them as separate strings like this?

  subprocess.run(["mpv", "--vo=tct", "--quiet", DirectLink])

Otherwise your terminal may be missing true-color terminal mode or the mpv in your distro doesn't have that output plugin. (You can check with "mpv --vo=help")

[kkirsche]

If, like me, you forget where to split the command and arguments, shlex.split in the standard library can split the raw string for you.

[Doxin]

Rule of thumb is every space, except ones you'd normally put between quotes. so e.g.

    foo quix-quiz "bar baz"

turns into

    ["foo", "quix-quiz", "bar baz"]

Though do note that you don't get an extra set of quotes on "bar baz" which is slightly confusing, but makes sense once you think about it a bit.