Auto: Automatically sets as many filters as required. Whenever a new feedback frequency is discovered, the first filter will be released to attenuate the new frequency. This means up to 8 notch filters will be added automatically, once all 8 are used if another feedback frequency is discovered the first filter will be overwritten.

Single: Activates the FBQ Functionality and will add up to 8 feedback filters, once all 8 are filled it will not add or replace any more.