KMix
KMix is an application to allow you to change the volume of your sound card.
12 Alternatives To KMix
3RVX
3RVX is a skinnable volume display and controller.
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Audio Sliders
Volume Control replacement that is five times smaller than its Windows counterpart.
Background Music
Control the audio on your Mac apps from the menu bar
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EarTrumpet
Volume Control for Windows
Power mixer
Power Mixer is a complete Windows volume control replacement.
QasMixer
QasMixer is a desktop mixer application for ALSA’s “Simple Mixer Interface”.
Sound Control
App-specific volume control
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Sound Lock
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Volti
Volti is an GTK+ application for controlling audio volume from system tray/notification area.
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Volume Icon
Volume Icon aims to be a lightweight volume control that sits in your systray.
Volumouse
From authors website:
Volwheel
VolWheel is a little application which lets you control the sound volume easily through a tray icon…