Tvheadend

22khz switching is only configurable by the choice of LNB in your satellite adapter configuration. Standard option is for Universal LNBF where 22khz switches between low/high local oscillator. The other LNB configuration that uses 22khz switch is an Advanced setting where 22khz can switch between a C band LNB 5150 LO and a Ku LNB 10750 LO. There is no direct setting available to manually choose 22khz on or off unfortunately.

So what this all means is that the 22khz will be switched on or off depending on the frequency that you enter provided the correct LNB setting has been chosen and actually matches your satellite hardware available.