I have just received and finished mounting of my QK-A027 and QK-AS03 too, and I’m facing the same troubles as you.
1) Over wifi with an iPad and iNavX, receiving the datas seems ok, but like you the AWS/TWS and AWS/TWD values are wrong (almost twice too high for the AWS/TWS than the value displayed on the Raymarine outdoor display).
2) I try to pass the QK-A027 AIS and SeaTalk datas to my Garmin GPSMap 525 plotter, but the plotter don’t see anything.
I have double check the wiring with the QK-AS03 Garmin Bridge, evrything is ok (NMEA OUT on QK-A027 >>> NMEA IN on QK-AS03 > TX on QK-AS03 >>> RX on Garmin, all others wires well connected as shown on the documentation wiring scheme).
I try all Garmin Communication settings too (Standard NMEA, High Speed NMEA, Garmin Data), but still nothing.
Would you have some clue ?
Best,
Mathieu