diff --git a/agb/examples/mixer_basic.rs b/agb/examples/mixer_basic.rs
index a9761403..c96103a7 100644
--- a/agb/examples/mixer_basic.rs
+++ b/agb/examples/mixer_basic.rs
@@ -17,7 +17,7 @@ fn main() -> ! {
     let mut input = ButtonController::new();
     let vblank_provider = agb::interrupt::VBlank::get();
 
-    let mut mixer = gba.mixer.mixer(gba.timers.timer0);
+    let mut mixer = gba.mixer.mixer(&mut gba.timers.timer0);
     mixer.enable();
 
     let channel = SoundChannel::new(DEAD_CODE);
diff --git a/agb/examples/stereo_sound.rs b/agb/examples/stereo_sound.rs
index 8050f602..0eda7f42 100644
--- a/agb/examples/stereo_sound.rs
+++ b/agb/examples/stereo_sound.rs
@@ -14,11 +14,11 @@ fn main() -> ! {
     let mut gba = Gba::new();
     let vblank_provider = agb::interrupt::VBlank::get();
 
-    let timer_controller = gba.timers;
+    let mut timer_controller = gba.timers;
     let mut timer = timer_controller.timer1;
     timer.set_enabled(true);
 
-    let mut mixer = gba.mixer.mixer(timer_controller.timer0);
+    let mut mixer = gba.mixer.mixer(&mut timer_controller.timer0);
     mixer.enable();
 
     let mut channel = SoundChannel::new(LET_IT_IN);
diff --git a/agb/src/sound/mixer/mod.rs b/agb/src/sound/mixer/mod.rs
index e6f598ff..80a009d6 100644
--- a/agb/src/sound/mixer/mod.rs
+++ b/agb/src/sound/mixer/mod.rs
@@ -15,7 +15,7 @@ impl MixerController {
         MixerController {}
     }
 
-    pub fn mixer(&mut self, timer: Timer) -> Mixer {
+    pub fn mixer<'a>(&mut self, timer: &'a mut Timer) -> Mixer<'a> {
         Mixer::new(timer)
     }
 }
diff --git a/agb/src/sound/mixer/sw_mixer.rs b/agb/src/sound/mixer/sw_mixer.rs
index f35bf6d5..d9229404 100644
--- a/agb/src/sound/mixer/sw_mixer.rs
+++ b/agb/src/sound/mixer/sw_mixer.rs
@@ -19,18 +19,18 @@ extern "C" {
     fn agb_rs__mixer_collapse(sound_buffer: *mut i8, input_buffer: *const Num<i16, 4>);
 }
 
-pub struct Mixer {
+pub struct Mixer<'a> {
     buffer: MixerBuffer,
     channels: [Option<SoundChannel>; 8],
     indices: [i32; 8],
 
-    timer: Timer,
+    timer: &'a mut Timer,
 }
 
 pub struct ChannelId(usize, i32);
 
-impl Mixer {
-    pub(super) fn new(timer: Timer) -> Self {
+impl<'a> Mixer<'a> {
+    pub(super) fn new(timer: &'a mut Timer) -> Self {
         Mixer {
             buffer: MixerBuffer::new(),
             channels: Default::default(),