init python:

    sfx = "sfx/"

    # Blips
    sfx_blip = sfx+"blip.wav"
    renpy.music.register_channel("blip", mixer="blip", loop=True, tight=False)
    
    def blip_play(on=False):
        if on:
            renpy.music.play(sfx_blip, channel="blip")
        else:
            renpy.music.stop(channel="blip")
    
    def blips(event, **kwargs):
        if event == "show" or event == "begin":
            blip_play(True)          
        if event == "slow_done" or event == "end":
            blip_play(False)

screen preferences():

    # ...

            frame:
                style_group "pref"
                has vbox

                label _("Text Volume")
                bar value MixerValue("blip")

                textbutton _("Test"):
                    action Play("blip", sfx_blip, loop=False)
                    style "soundtest_button"