We suggest performing a manual loudspeaker calibration instead of automatic setup. There are two parts to the calibration, distance and level.
For distance, simply measure and record the distance from each loudspeaker to the primary listening position. Enter these distances in the loudspeaker setup menu.
To set levels, you will utilize the receiver’s internal test tones and an SPL meter. There are a number of SPL meter applications for both iOS and Android. They may not be as accurate as a standalone, dedicated meter but they’ll certainly work for this.
Position the meter/phone near the ear level of the primary listening position. Start the test tone level calibration in the loudspeaker setup menu and adjust the level up or down for each loudspeaker so that the SPL meter reads ~75 dB SPL, C-weighted. Let the system cycle or manually cycle through each of the loudspeakers. When calibrating the subwoofer level, it is beneficial to move the meter/phone across multiple seating positions near primary as the bass level typically varies by location in the room.
As an aside, THX recommends setting all loudspeaker sizes in the menu to Small as the receiver will perform the bass management and route appropriately to the subwoofer.