digital decoding

I'm having a hell of a time trying to set up my RTL-SDR V3 to decode my local police departments, each one functions on a P25 conventional single frequency. I've seen too many videos on Youtube and have read countless hours of forums and articles on how to set this up to absolutely no avail...

I have a uniden bearcta scanner with a discriminator output mod. It wokrs perfectly decoding audio with DSDplus in windows. However when I try to use it with DSplus in Linux i get the error Syncing voice output stream An error occured while using the portaudio output stream...