Surround : Pro Tools Setup for Surround : Default I/O Selectors in I/O Setup : Default Path Order for 5.1 Tracks

Default Path Order for 5.1 Tracks
You can specify the default track layout for all new 5.1 format paths you create.
To choose a new default 5.1-format path order (track layout):
1 Choose Setup > I/O.
2 Click the Output tab.
3 Use the 5.1 Default Path Order setting to select the track layout you want (Film, SMPTE/ITU, or DTS/ProControl Monitoring).