GIG Player - sustain pedal doesn't catch residual resonance after key release

Hi there, I'm testing `lmms-1.2.0-rc6-linux-x86_64.AppImage` on openSUSE Leap 15.0. I'm really excited to see the GIG Player, and I've been testing it with [Maestro Concert Grand v2](http://linuxsampler.org/instruments.html) via an M-AUDIO 88es controller and an OnStage sustain pedal.

The problem is that the sustain pedal works, but not like a real piano. After hitting some keys, releasing the keys, and then immediately depressing the sustain pedal while there is still residual resonant sound, it does not sustain the resonant sound.

The sustain pedal **does** work naturally with the same GIG file via `qsampler` / LinuxSampler.

Thanks a lot for LMMS!

Start by reproducing the behavior in lmms-1.2.0-rc6-linux-x86_64.AppImage with the Maestro Concert Grand v2 GIG file, M-AUDIO 88es controller, and OnStage sustain pedal. Compare the GIG Player result with qsampler/LinuxSampler; the issue is done when pressing sustain during residual resonance preserves that sound as it does in LinuxSampler.

Written by the indexing model from the issue text.