This is strange behavior for Studio One and we have not had any other reports of this happening. Here is what you might want to try:
1. Check your mouse settings and re-install the driver for your mouse.
2. Press ctrl, alt, delete and open the Task Manager. Go into "Startup" and try disabling startup items as a 3rd party app could be creating the issue.
3. Do a full scan of your system for Malware.
4. Try removing the settings files from Studio One. As this will also remove your keyboard shortcuts, it may resolve your issue. Here are instructions:
Go to Help>Open Settings folder.
Copy the contents of the folder over to a folder on your desktop.
Close S1 and delete the contents of the settings folder with the exception of the user.license file as well as the "Extensions" folder.
Open S1 and go to Studio One>Options (Preferences on a Mac) to reconfigure your settings.
Test to see if the problem is resolved. If it is not, please feel free to copy your settings files back over from the backup that you created in step 2.
*If you are missing presets or Sound Sets after doing this, simply double-click one of your Sound Sets under Documents>Studio One>Sound Sets.
5. Uninstall and re-install Studio One.
If the problem persists, try using a different mouse. If you still have the issue, please feel free to submit a support ticket from within your my.presonus.com account under the "Support" tab.