Ultimately if you want to fight this you're going to have to be prepared to file a Petition for Declaratory Ruling with the FCC. The FCC will then send a letter to the landlord, telling them they are investigating the matter, and ordering them not to proceed with any action against you under they are done. After completing this, they will then issue a Ruling on whether or not the landlord's restrictions are legal or not (it sounds like they are not).
There are instructions on the FCC site on how to do this; they are not too difficult.
It seems the landlord doesn't realize that, even though they own the property, they cannot lease it out under any conditions they please, if these conditions violate Federal law. It's not much different them having them decide that they would rather not rent to minorities; that pesky 1964 Civil Rights Act you know.
After the FCC issued the Ruling, you would have a powerful weapon in a lawsuit against the landlord were they to hassle you further.
And oh, this FCC Rule, mandated by the 1996 Telecomm. Act, is specifically targeted to prevent the type of cushy Landlord/Cable Co. culusion exampled above.