I have the stock Visteon Cassette/Cd changer control in my 2001 Ford Lightning. It seems that certain stations will change to a lower tone on and off. Is this a reception problem, a head unit problem or a speaker problem. It is a little hard to explain but it is almost like the speed sensitive volume control is working overtime only it is making things softer. This is all when speed sensitive volume control is set to 0 or off. This only seems to happen drastically to one station and not as bad to a few other stations. All of these stations worked fine on 4 other stock car stereo systems.

Help?