I want to use a set up devil streaming system via a new router, but I can't find an option to change the WIFI/password.

1st option (if neither the WIFI name nor the WIFI password are changed)
In order to be able to use a set-up devil Streaming System immediately with a new router, please transfer the WIFI name (SSID) and the WIFI password of the old router to the new router.

2nd possibility (if WIFI name and/or WIFI password are changed)
Alternatively, simply set up devil Streaming again by selecting the "System Maintenance" item in the "Settings" menu and then the "Room Configuration" option via "Reset". The setup wizard will then start. Your data (favourites, etc.) will be retained.