I don't know how reliable the software is now since the official website doesn't exist anymore. The problem you're having might be related to the lack of software updates and compatibility. Also, when it comes to VoIP, you have to make sure that the connection is strong.
It's also recommended that when you call your bank to do it from a fixed standard line just to avoid this kind of things and avoid other snooping on your connection.
You can try Route Test but I don't know how reliable it is.