Yes! Sound Siphon works with all of your applications, including sandboxed applications.
- Sound Siphon can capture audio of sandboxed apps
- Sound Siphon devices can be used in sandboxed apps
- Sound Siphon is, itself, sandboxed and follows Apple’s sandboxing rules.
Below is Sound Siphon being used with QuickTime Player to capture audio from Safari. Both of these apps are sandboxed.