I'm trying to extract data from an IRIS database into SQL server with SSIS using the ODBC driver: InterSystems ODBC35 (ODBC-2023.1.0.229.0-win_x64.exe)

I have Unicode turned off in the ODBC settings.
I'm getting strange results - with some tables the SSIS ODBC connector will work but the ADO.net connector - using the same ODBC driver will. For other tables it's the other way round. The ADO.net sees the data as unicode and won't allow me to insert it into a non unicode table but ODBC will be fine.