I am having a hard time staying locked on to the control channel. But i have no issues listening to calls when i am locked on. i have 5 RTL-SDR dongles and my area only has 3 talk frequencies not including 2 control frequencies. my question is how do i setup SDRTRUNK to monitor these frequencies. when i use NBFM i get nothing but when i use p25p1 i get nothing. any ideas?