Hi.

Usually there are jumpers inside remote circuit and on IR sensor, by changing them you will exclude the possibility of IR interference.

IR is a light signal, therefore it is highly unlikely that the problem is coming from your neioghbors, the problem looks more like a defective IR sensor on the fan, that is not a too unusual fault.

I suggest calling Hunter Ceiling at the number listed on the owners manual to see what they think about the problem.

Regards.