I'm in amateur radio and radio frequency interference is a BIG deal near airports. Essentially, anything that is wireless can interfere with airplanes.
That would explain the TV complaints, but computerized sewing machines???? That's a new one for me! As long as the sewing machine is not sending or receiving wireless transmissions, there is nothing to worry about.
If we start getting sewing machines that act like iPads... all bets are off.