Managed to finally sort out the problem & get PDW working.
If anybody else has the same type of problem, then check that your pc has permissions to allow PDW to access your microphone.
This was the problem with mine, soon as I changed the permissions from no to yes, PDW started working perfectly.
I can decode FLEX with no problem, but POCSAG still gives garbled text on the screen

I thought that doing the discriminator mod on my BCT15X would have cured this but unfortunately, it hasnt. So that's the next thing to try and figure out.
FLEX = great decode
POCSAG = garbled decode (for now until I can find out why)
Thanks to those that helped with suggestions etc on curing the original problem

Regards
welshmonitor