Thank you for the information.
Can you check the following points please:
1, Make sure your AIS transponder output AIS messages via RS422 port(some devices need to enable this…)
2, Make sure the baud rate on both devices are the same(you need install the configuration tool to check this). More details about the configuration tool can be found from the manual(chapter 4):
https://www.quark-elec.com/doc/QK-A034_manual.pdf
3, Please make sure your A034 has the latest firmware:
The latest version can be download from: https://www.quark-elec.com/downloads/drivers/
Hope above helps.
Let us know if you need further helps.