* Solved an issue where the app could start to produce noise after a long period of use (over 12 hours at 48000Hz for example).
* Pressing Enter when changing the reference pitch did not do anything on phones. Solved.

The app will attempt to recover the digital purchase receipt when it is not present on start-up. This should solve the problem some people have been experiencing where the app goes in trial mode after months of use.

Bug fix.

* Added a recording option to the stand-alone mode
* Prevented audio feedback loop in stand-alone mode when no headphones are connected. A message is also displayed when no headphones are connected.

Fixed MIDI input problem.

Aeolian and Mixolydian were swapped. Solved.