Possible bug AMP section (Effects)

If you choose an Amp preset like "Combo Warm," then alter one of the settings, such as Mix or Drive settings, the title of the preset wil become italic to indicate that it has been altered. To reset the Amp preset, right click on the preset title ("Combo Warm"), or left-click on the preset title and choose the bottom entry in the popup list, "Reset (discard modifications)."

But yes, it does seem that unlike many parameters in other effects, right-clicking on a particular parameter in the Amp effect and then clicking Reset, has no effect on the parameter, whether it has been altered by the user or not.

Potential bug and link to this forum topic have been reported from Pianoteq-->Options-->About-->Feedback and bug reports

I received a reply and explanation about this issue (which is not really a bug) from Modartt team member Julien Pommier.

The Reset button is intended to restore the value of a parameter to the instrument preset's saved values.

If a user changes something about an instrument preset, such as enabling or changing one of the three available effects, the designation "(modified)" will be appended to the instrument preset's name. If the modified instrument preset is then saved, the Reset button associated with the effects' parameter values will function, will restore the parameter to the value that was saved with the instrument preset.

So, adding the "Amp" effect within a particular instrument preset (factory or user preset, it doesn't matter), changes that instrument preset. The Reset button cannot restore an Amp parameter's original value because the Amp effect itself (including the Amp effect parameters' values) have not (yet) been stored (saved) with or within the currently-active instrument preset.

This is a case where the complexity of interactions between the various functionalities of Pianoteq can produce an effect that can be confusing, until the reasons for that behavior or effect are known or understood.