So it is not even decoding the audio?
The issue is that with conventional systems (non-trunked), there is no control channel to tell DSD where to jump. So, you should be hearing the audio fine on the frequency you are parked on, but as far as being able to monitor 5 conventional frequencies at once, I dont think that is possible with DSD. You can try entering them as a trunked system in the .frequencies file, and see if it just jumps around until it finds an active channel
Edit: Theres a NXDN conventional system that Ive been monitoring for DB updates - there are like 10 frequencies, but I can only monitor one at a time, since it isnt trunked and DSD doesnt have any info to jump to active channels nor a scan function. The only possibility is setting it up as a trunked system, but I dont know if that would work considering there is no LCN or other needed info.