It probably is not the landlord's fault.
If you are dealing with very strong local radio signals, all you can do is sell or throw away any electronics that are manufactured in unshielded plastic boxes, and only buy high quality electronics in shielded metal boxes from stores where you can easily return items that fail in your environment -- and even then, you may need to take extra steps such as applying ferrite RFI suppression chokes to all input and output wires.
(If you are wondering if you can sue the radio station or ask them to replace your devices, you can't. They have a license to cause this kind of problem, and at least in the USA, the FCC has decided that RFI is typically the product manufacturer's fault and not the radio station's fault).
What you have is a very strong radio signal around devices that aren't designed to reject it.
This problem is called Radio Frequency Interference. In the early days of AM radio, people made crystal radios that did not need electricity at all -- consisting of a tuned filter and a non-linear junction supplied by a crystal or, in modern children's kits, a modern diode -- the result was a signal strong enough to hear in sensitive headphones. If the signal is strong enough, you don't need the tuned filter, and such signals may similarly be received unintentionally by cheap unshielded modern electronics.
Ideally computer speakers should be in metal boxes instead of plastic boxes. The metal box acts as a Faraday cage to shield the audio amplifier from undesired radio signals that might otherwise be received by the amplifier circuit. You can put rfi suppression ferrite beads on all input and output leads to the speakers to block the radio signal from travelling down the speaker or power wires, but if the speakers are in plastic boxes that may not help and buying a better model may be more time and cost effective.