It's a phenomenon I've encountered on a number of occasions in my marine industry career. The causes are simple and easily understood, while the solutions can be maddeningly elusive. The side effects can be everything from static or distortion on an otherwise high-quality television screen to humming or buzzing on a VHF radio, and in some cases, malfunctions in autopilot control systems, some of which may be dramatic. I've troubleshot more client complaints that start with the observation, "when I key the microphone the boat makes a hard turn to port/starboard," than I can recall.
Two routes lead north along the Inside Passage in lower British Columbia, from urbanity, highways, and talk shows on the radio to the welcome wilderness of central and northern British Columbia. Both offer challenges and the opportunity to take a beating from the sea. One is a long haul through often stormy waters, but with hardly a need to change course for a couple of days, while the other curls among islands and waterways, turns from narrow channels to major inlets and vessels glide past snow-topped peaks along the shore.