The FBQ2496 comes with all filters set to PEQ. In order to use learn mode, so the unit automatically assigns single shot filters to feedback frequencies the steps in this guide should be followed:   1) Press and hold the PEQ button until the display screen reads 'P20'. 2) Then using the jog wheel set this display to 'P 0'. This makes space for the single shot filters. 3) Press the LEARN button. 'S 0' should appear on the display screen. 4) Using the jog wheel set how many filters you want to be single shot filters. In this case 20. 5) Press the learn button again and the display screen should read 'run'. 6) Turn up the system volume and as feedback occurs the signal shot filters will kick in automatically to cut the feedback. As each of the numbers 1-20 light up this signifies a single shot filter being assigned to that specific feedback frequency.    To clarify the unit can only produce 20 filters per channel. So if, for example, you have 13 filters set for PEQ the maximum single shot filters that can be assigned is 7.