Is there a way to combine numbers in the call sign? For example with Southwest 3254, P2A says/understands 3-2-5-4 instead of 32-54 like in real life. I thought it was possible in the past but I might be confusing it with Radar Contact.

From the manual it seems there is option 1 only.

I am not sure if this is of any help, but here is my comment

 

I use call sign  PAPA ES4 and that works well. 

 

Try entering Southwest Three Two Five Four  (words instead of numbers)

Southwest Thirty Two Fifty Four used to work.

I'll see what's going on and get it fixed for the next update. 

When you enter the call sign in the Config Section, don't use the spelled out numbers as P2A interprets Thirty as Tango Hotel India .....

So Check the Airline box, enter Southwest in the Mfg/Airline text box and 3254 in the Tail Number/Flight text box.

Then once I get the bug fixed, it should work.

Dave

Been using airline and 121

with speech Pilot2ATC accepts my airline one twenty one nicely