An external would improvement, I guess the reception area in your location and the channel strength you are trying to receive, plays a part of course.
My wife’s Fiat 500 has a roof arial as standard, but in areas where the terrain is hilly, you can hear the station struggling to maintain its fix.
When it’s raining the reception is not the greatest either.
Is it the arial / head unit / poor weather condition, or probably a combination of all of them, who knows ?.
Today a lot of people prefer to stream or listen to their own choice of music from their phones etc, so less likely that money will be spent on installing a really good quality radios receiver and arial set up

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We always have the radio playing some type of relaxing music playing, at a low volume from the radio in the back ground when driving.
It kind of suits the relaxing peaceful drive of an EV in some way

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