Inheritance-like problem in Rust

inheritance.rs

/// Problem: there is a lot of duplication in function implementations.
/// The two types should have the same interface but use a different underlying type.
///
/// How can I reduce the amount of duplication and avoid having to update the code in two places?
/// In other languages, I would define a base class which accepts a generic type for the `SoundSource`s
/// but I don't know how to solve this sort of problem in Rust.

struct Sound {
    // Shared properties
    is_playing: bool,

    // Sort of shared
    source: Option<SoundSource>,
    spatial: Option<SpatialSoundSource>,
}

impl Sound {
    fn play(&mut self) {
        self.stop();
        self.play_later();
    }

    fn stop(&mut self) {
        if let Some(source) = self.source {
            source = SoundSource::new();
        }
        if let Some(spatial) = self.spatial {
            source = SpatialSoundSource::new();
        }
        self.is_playing = false;
    }

    fn play_later(&mut self) {
        if let Some(spatial) = self.spatial {
            source.reset_position();
        }
        self.source.play_later();
        self.is_playing = true;
    }
}