The KPA doesn't seem to track changes to volume while in tuner-mode when the tuner is activated using either the mode-knob or an external switch. Going back to browse-mode the tuner-display may remain active when volume is turned up. I normally avoid the problem by changing the range for the volume pedal to avoid "double-activating" (by knob+pedal) the tuner accidentally, but it's a pain when i forget and it has to be done manually for every single rig.
To reproduce:
Start in browse-mode with a rig with default volume-pedal-range (so that the tuner activates at 0 vol) and volume pedal turned up to max then ...
1. Switch the mode-knob to tuner
2. Take the volume-pedal to 0 (mute)
3. Switch mode back to browse. The rig is shown on the display as expected ... but
3. Press pedal to increase volume, and as soon as the volume increases the display switches back to the tuner, but audio is no longer muted despite the tuner being configured to mute. The KPA now remains locked in tuner-mode regardless of the position of the volume pedal and it requires interaction via the front-panel to restore normal operation.
If I use an external plain pedal/switch to toggle the tuner it works the same as using the front-panel knob except that the KPA can't be restored to normal operation with 2 hits on the pedal. I have to reach for the mode-knob. Somehow a pedal configured to activate the tuner doesn't seem equivalent to switching the tuner on/off on the KPA front-panel.
I use the KPA with a Behringer FCB1010 w/uno4kemper (1.2) and an extra toggle switch for the tuner. In addition to better tracking of anything happening to the volume-pedal while in tuner-mode I'd really appreciate a global setting to disable tuner-activation at 0-volume. I prefer to be able to browse/switch rigs with the volume off without having to edit every single rig I use. I'm currently running kaos 2.3.1b but the problem has been the same with every firmware-release I've tried in the past 8 months.