diff --git a/src/host/wasapi/device.rs b/src/host/wasapi/device.rs
index fd9840a..e9e53e6 100644
--- a/src/host/wasapi/device.rs
+++ b/src/host/wasapi/device.rs
@@ -7,7 +7,7 @@ use std::ops::{Deref, DerefMut};
 use std::os::windows::ffi::OsStringExt;
 use std::ptr;
 use std::slice;
-use std::sync::{Arc, Mutex, MutexGuard, atomic::Ordering};
+use std::sync::{Arc, Mutex, MutexGuard};
 
 use BackendSpecificError;
 use DefaultFormatError;
@@ -72,7 +72,7 @@ use super::winapi::um::mmdeviceapi::{
 };
 
 use crate::{traits::DeviceTrait, BuildStreamError, StreamData, StreamError};
-use super::{stream::{Stream, AudioClientFlow, StreamInner, Command}, winapi::um::synchapi};
+use super::{stream::{Stream, AudioClientFlow, StreamInner}, winapi::um::synchapi};
 
 pub type SupportedInputFormats = std::vec::IntoIter<SupportedFormat>;
 pub type SupportedOutputFormats = std::vec::IntoIter<SupportedFormat>;
@@ -267,7 +267,7 @@ pub unsafe fn is_format_supported(
         // has been found, but not an exact match) so we also treat this as unsupported.
         match (result, check_result(result)) {
             (_, Err(ref e)) if e.raw_os_error() == Some(AUDCLNT_E_DEVICE_INVALIDATED) => {
-                return Err(SupportedFormatsError::DeviceNotAvailable);
+                Err(SupportedFormatsError::DeviceNotAvailable)
             },
             (_, Err(_)) => {
                 Ok(false)
@@ -486,7 +486,7 @@ impl Device {
             };
 
             // If the default format can't succeed we have no hope of finding other formats.
-            assert_eq!(try!(is_format_supported(client, default_waveformatex_ptr.0)), true);
+            assert_eq!(is_format_supported(client, default_waveformatex_ptr.0)?, true);
 
             // Copy the format to use as a test format (as to avoid mutating the original format).
             let mut test_format = {
@@ -508,7 +508,7 @@ impl Device {
                 test_format.nSamplesPerSec = rate;
                 test_format.nAvgBytesPerSec =
                     rate * (*default_waveformatex_ptr.0).nBlockAlign as DWORD;
-                if try!(is_format_supported(client, test_format.as_ptr())) {
+                if is_format_supported(client, test_format.as_ptr())? {
                     supported_sample_rates.push(rate);
                 }
             }
diff --git a/src/host/wasapi/mod.rs b/src/host/wasapi/mod.rs
index ecf7d7a..c7fc241 100644
--- a/src/host/wasapi/mod.rs
+++ b/src/host/wasapi/mod.rs
@@ -61,8 +61,9 @@ fn check_result_backend_specific(result: HRESULT) -> Result<(), BackendSpecificE
     match check_result(result) {
         Ok(()) => Ok(()),
         Err(err) => {
-            let description = format!("{}", err);
-            return Err(BackendSpecificError { description });
+            Err(BackendSpecificError { 
+                description: format!("{}", err),
+            })
         }
     }
 }
diff --git a/src/host/wasapi/stream.rs b/src/host/wasapi/stream.rs
index decada6..72a863f 100644
--- a/src/host/wasapi/stream.rs
+++ b/src/host/wasapi/stream.rs
@@ -1,9 +1,6 @@
 use super::check_result;
-use super::com;
 use super::winapi::shared::basetsd::UINT32;
-use super::winapi::shared::ksmedia;
-use super::winapi::shared::minwindef::{BYTE, DWORD, FALSE, WORD};
-use super::winapi::shared::mmreg;
+use super::winapi::shared::minwindef::{BYTE, FALSE, WORD};
 use super::winapi::um::audioclient::{self, AUDCLNT_E_DEVICE_INVALIDATED, AUDCLNT_S_BUFFER_EMPTY};
 use super::winapi::um::handleapi;
 use super::winapi::um::synchapi;
@@ -13,17 +10,13 @@ use super::winapi::um::winnt;
 use std::mem;
 use std::ptr;
 use std::slice;
-use std::sync::Mutex;
 use std::sync::mpsc::{channel, Sender, Receiver};
-use std::sync::atomic::AtomicUsize;
 
 use std::{sync::{Arc},
 thread::{self, JoinHandle}};
 use crate::traits::StreamTrait;
 
 use BackendSpecificError;
-use BuildStreamError;
-use Format;
 use PauseStreamError;
 use PlayStreamError;
 use SampleFormat;
@@ -257,7 +250,7 @@ fn stream_error_from_hresult(hresult: winnt::HRESULT) -> Result<(), StreamError>
     Ok(())
 }
 
-fn run_inner(run_context: RunContext, data_callback: &mut dyn FnMut(StreamData), error_callback: &mut dyn FnMut(StreamError)) -> () {
+fn run_inner(run_context: RunContext, data_callback: &mut dyn FnMut(StreamData), error_callback: &mut dyn FnMut(StreamError)) {
     unsafe {
         'stream_loop: loop {
             // Process queued commands.