This may be an unpopular opinion but if you're not using FMPx with DSDPlus you're probably not going to get the best experience. Both in decoding and audio. I am not saying that you won't get a good experience at all. But you won't get the benefit of things like the FCC frequency data displayed. Single receiver trunk tracking, or any trunking at all. Or at least not as easily. When they are linked DSDPlus becomes "frequency aware" allowing it to also send things back to FMPx like when to search for a lost control channel.
There's a lot of benefits to it if you can use it.
There's a lot of benefits to it if you can use it.