May 07 21:57 2016, Tony Langdon wrote to Markus Reschke:
TL> My Fritzbox can be configured for DSL or cable, I'm using it in a TL> "cable" configuration with an external DSL modem, because the TL> Fritzbox's modem doesn't work well on long lines.
I'd guess AVM optimized the firmware (the part for the DSL chipset) for DSLAMs commonly used in Germany. By "Cable" I've meant the models with built in cable modem. I'm so used to the term "external modem" that it didn't occur to me that "cable" could be the ethernet cable to the modem :)