After resetting Symphony I/O's Output Routing, the Speaker Sets feature no longer works

The Speaker Set assignments are actually just Presets that adjust the Output Routing selections to the appropriate Outputs.

If the Output Routing Tab is Reset , the Speaker Sets are still assigned to Touchpads or set in Software but no longer assigned to the correct Output

Solution: Go to Output Tab and set Speaker to Stereo from the drop down menu.  Then, switch it back to desired number of Speaker Sets and the signal will pass as expected.