> I'm looking for any tutorials/source code examples which deal with > controlling the onboard Synth volume from a BSlider. I'm having a few > problems. I have started to tinker with the midi kit so anything > suitable for a noob would do! :o) By "onboard synth" do you mean the software synthesizer, or the synthesizer on your soundcard (if any)? The master volume of most MIDI devices can be controlled using a SysEx message -- f0 7f 7f 04 01 LSB MSB f7 where LSB is the "fine" part of the setting, and MSB is the "coarse" part, 0-127 each. I'm not sure if FluidSynth responds to this -- it has more bugs than features -- but give it a try anyway. If you want to change the volume of an on-board synth (on a soundcard), that can also be done via the soundcard's mixer. I'm not sure if there's any standardized way in Haiku for manipulating that though... The slider part is pretty easy -- the member function SetValue(int32 val) in your BSlider gets called every time the slider's value changes. Assuming you've created a derived class that defines this function, you can do the necessary stuff inside SetValue(). The function is called continuously while you drag the slider, so it updates in real-time. For instance: class SLIDER : public BSlider { public: void SetValue(int32 value) { BSlider :: SetValue(value); /* Send the SysEx message or whatever here */ } } - Cyan