Nowhere in your initial post do you mention nor show that the AStream_NewData sub that is located in you Main module is called from your astreams_NewData sub located in your class. From your initial post, I don't see nor are you showing us (via logs/pop ups, etc.) that astreams_NewData is actually called. Just from that little bit that you are posting, one would gather that you opened an AsyncStream in Main and initialized it with "AStream" as the prefix for the callback subs and you created another AsyncStream in you class that has "astreams" configured as the prefix for you callback subs. Nowhere though do you show us where / how you are initializing your AsyncStreams, so I'm even guessing that you named you prefixes such without accidentally misspelling them.
What is not easy to test? You can always use log() to log anything and everything, especially if you are not sure if a certain code path even gets executed/called.