Question about AVM FRITZ!Box 6690 Cable

No, there is no free choice of modem in Switzerland. In my case, the box could not be activated (Sasag Kabelkommunikation AG in Schaffhausen), although my network operator sometimes includes the Fritz!Box 6690 with new subscriptions. Moreover, it is hardly worth returning it to Digitec because 10% of the sales value is charged. My tip: The Fritz!Box 4060 is a pure WLAN router with all Fritz functions and is cheaper than the Fritz!Box 6690.

"flashcable" from GIB Solution sends me a modem with which I can connect any wifi router, supposedly this is the only way because then the Fritzbox does not have to be set up separately. This is the only way I can swap the Fritbox 6660 for a 6690 with stronger wifi.