This is a bug when using Pro Tools 12.4 with an Omni IO. The Audition path ( in Setup > IO Setup > Output ) is set to the designated monitor output. When toggling the 'alt' button on the front panel of the Omni IO whilst in the import audio dialog window, the auditioned audio will remain being sent to the Main speakers connected to physical output 1 and 2 in stead of the Alt speakers, in my case connected to output 7 ...more »
My Main Output is a 5.1 Output. When setting my Audition Path to that, it seems to 'downmix' to a mono output on Channel 3 (Centre) when previewing in any AudioSuite Plug Ins.
Workspace Auditioning is fine though & plays out of L&R. Surely that's the same Audition Path?
Ive tried trashing Prefs & still the same