When analogFxoFakePolarityEnabled is set to YES, this parameter will specify the signal level threshold in dbov uppon which the analog driver should consider that the activity on the fxo line is due to coming fsk caller-id. If signal level on the fxo line is greater or equal to this treshhold value, the driver will fake polarity reversed on the line in order to advertise coming fsk caller-id.

Valid values are: 0 to - 18. Recommended value is -12