diff --git a/src/lib.rs b/src/lib.rs
index 70b6d46..d93e588 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,5 +1,4 @@
 #![allow(clippy::uninlined_format_args)]
-#![cfg_attr(feature = "simd", feature(portable_simd))]
 
 mod error;
 mod standalone;
diff --git a/src/utilities.rs b/src/utilities.rs
index d233c9c..f8bc554 100644
--- a/src/utilities.rs
+++ b/src/utilities.rs
@@ -1,6 +1,3 @@
-#[cfg(feature = "simd")]
-use std::simd::{f32x16, i16x16, SimdInt};
-
 /// Convert an array of 16 bit mono audio samples to a vector of 32 bit floats.
 ///
 /// This variant does not use SIMD instructions.
@@ -18,40 +15,6 @@ pub fn convert_integer_to_float_audio(samples: &[i16]) -> Vec<f32> {
     floats
 }
 
-/// Convert an array of 16 bit mono audio samples to a vector of 32 bit floats.
-///
-/// This variant uses SIMD instructions, and as such is only available on
-/// nightly Rust.
-///
-/// # Arguments
-/// * `samples` - The array of 16 bit mono audio samples.
-///
-/// # Returns
-/// A vector of 32 bit floats.
-#[cfg(feature = "simd")]
-pub fn convert_integer_to_float_audio_simd(samples: &[i16]) -> Vec<f32> {
-    let mut floats = Vec::with_capacity(samples.len());
-
-    let div_arr = f32x16::splat(32768.0);
-
-    let chunks = samples.chunks_exact(16);
-    let remainder = chunks.remainder();
-    for chunk in chunks {
-        let simd = i16x16::from_slice(chunk).cast::<f32>();
-        let simd = simd / div_arr;
-        floats.extend(&simd.to_array()[..]);
-    }
-
-    // Handle the remainder.
-    // do this normally because it's only a few samples and the overhead of
-    // converting to SIMD is not worth it.
-    for sample in remainder {
-        floats.push(*sample as f32 / 32768.0);
-    }
-
-    floats
-}
-
 /// Convert 32 bit floating point stereo PCM audio to 32 bit floating point mono PCM audio.
 ///
 /// This variant does not use SIMD instructions.
@@ -73,46 +36,6 @@ pub fn convert_stereo_to_mono_audio(samples: &[f32]) -> Result<Vec<f32>, &'stati
         .collect())
 }
 
-/// Convert 32 bit floating point stereo PCM audio to 32 bit floating point mono PCM audio.
-///
-/// This variant uses SIMD instructions, and as such is only available on
-/// nightly Rust.
-///
-/// # Arguments
-/// * `samples` - The array of 32 bit floating point stereo PCM audio samples.
-///
-/// # Returns
-/// A vector of 32 bit floating point mono PCM audio samples.
-#[cfg(feature = "simd")]
-pub fn convert_stereo_to_mono_audio_simd(samples: &[f32]) -> Result<Vec<f32>, &'static str> {
-    let mut mono = Vec::with_capacity(samples.len() / 2);
-
-    let div_array = f32x16::splat(2.0);
-
-    let chunks = samples.chunks_exact(32);
-    let remainder = chunks.remainder();
-    for chunk in chunks {
-        let [c1, c2] = [0, 1].map(|offset| {
-            let mut arr = [0.0; 16];
-            std::iter::zip(&mut arr, chunk.iter().skip(offset).step_by(2).copied())
-                .for_each(|(a, c)| *a = c);
-            arr
-        });
-
-        let c1 = f32x16::from(c1);
-        let c2 = f32x16::from(c2);
-        let mono_simd = (c1 + c2) / div_array;
-        mono.extend(&mono_simd.to_array()[..]);
-    }
-
-    // Handle the remainder.
-    // do this normally because it's only a few samples and the overhead of
-    // converting to SIMD is not worth it.
-    mono.extend(convert_stereo_to_mono_audio(remainder)?);
-
-    Ok(mono)
-}
-
 #[cfg(feature = "simd")]
 #[cfg(test)]
 mod test {
@@ -126,27 +49,3 @@ mod test {
         assert!(mono.is_err());
     }
 }
-
-#[cfg(feature = "simd")]
-#[cfg(test)]
-mod test_simd {
-    use super::*;
-
-    #[test]
-    pub fn assert_stereo_to_mono_simd() {
-        // fake some sample data
-        let samples = (0u16..1028).map(f32::from).collect::<Vec<f32>>();
-        let mono_simd = convert_stereo_to_mono_audio_simd(&samples);
-        let mono = convert_stereo_to_mono_audio(&samples);
-        assert_eq!(mono_simd, mono);
-    }
-
-    #[test]
-    pub fn assert_stereo_to_mono_simd_err() {
-        // fake some sample data
-        let samples = (0u16..1029).map(f32::from).collect::<Vec<f32>>();
-        let mono_simd = convert_stereo_to_mono_audio_simd(&samples);
-        let mono = convert_stereo_to_mono_audio(&samples);
-        assert_eq!(mono_simd, mono);
-    }
-}