When I press the sustain pedal in Sunday Keys for Ableton it turns off any

When you press the sustain pedal in Sunday Keys for Ableton if it turns off any sound you have on in the Piano 1 column or it turns on patches you didn't have selected, you can fix this by changing a few settings.

In Preferences > Link/Midi tab, find the keyboard you are using and turn off “remote.” This will keep your keyboard hardware from interfering with the mappings in Ableton. If you are mapping controls to Ableton via your keyboard, you will want to keep remote turned on. Select the MIDI rectangle in the top right corner, then click the drop down arrow in the top left corner to view the assigned MIDI mappings. There you can check if the clip launch buttons are mapped to your sustain and delete those mappings.

You can see how to map controls to your midi controller on the Sunday Keys for Ableton Video Resource page.