How to improve your audio quality on Apple CarPlay

Apple CarPlay gives you a simple solution to listen to your favorite music from Spotify or Apple Music in your vehicle. However, it is not guaranteed to give you the best sound your car can produce. Your iPhone may deliver a lower-quality stream to the stereo than you expect, with settings that sound great through your headphones but terrible through your car speakers.

There’s no magic solution to this problem, given how widely car speakers differ. The quality of the original music will obviously play its part, but the way your iPhone connects to your car also has an impact. Rather than upgrading your speaker system immediately, you can try some simple tweaks to improve audio quality when using Apple CarPlay.

Wireless CarPlay is the most convenient option for most people. You don’t even have to take your iPhone out of your pocket for your car to connect and start playing your favorite songs. Unfortunately, this is not the best option for those who demand the best music quality.

Take it from Apple: wired is best for your music. Apple’s guidelines for Apple Music via CarPlay confirm that only a wired USB connection will allow you to play lossless audio. Lossless audio is compressed without losing any of the original audio data, meaning you don’t lose detail. A wired connection means you can switch to lossless streams, provided you have an active Apple Music subscription and have enabled this option.

Technically, it all depends on the codec. Apple uses LPCM for audio on wired CarPlay connections, but switches to AAC-LC when using wireless CarPlay. LPCM carries uncompressed digital audio, so a lossless ALAC track from Apple Music can be transmitted to your car without lossy compression. Wireless CarPlay must first encode the audio in AAC-LC, using lossy compression to reduce the bit rate and removing some of the original audio data in the process.

The end result is lower quality sound, but that doesn’t mean Wireless CarPlay automatically sounds bad. Whether you hear the difference will depend on your car’s audio system and your ears. The speakers and amp (if your car has them) have a huge influence here. Additionally, other distractions, like road noise, will never provide an ideal environment for listening to music.

A wired connection can only preserve the quality it receives in the first place. When you stream content from Apple Music or Spotify while driving, your mobile connection won’t be perfect. You regularly move from cell tower to cell tower and move in and out of cell coverage. Connection drops mean quality drops: CarPlay can’t counter this, even over USB.

This problem is easily solved by downloading your usual playlists to your iPhone before you leave. Apple Music lets you choose your preferred quality setting for downloads, including lossless at 24-bit/48kHz. This, while using wired CarPlay, will give you the best possible sound quality on the platform. If you’ve already downloaded your music in lower quality, Apple recommends deleting it from your phone and downloading it again to get the lossless version.

You can also listen to lossless audio on other platforms, including Spotify, which allows Premium subscribers to download lossless audio at 24-bit/44.1kHz using FLAC. Otherwise, Spotify will automatically adjust the quality of your streaming based on your connection; downloading your playlists will prevent this from happening.

Since lossless audio files will take up much more storage than their compressed counterparts, make sure you have enough space available. Another benefit of downloading your music is preserving your data plan, as lossless streaming uses a huge amount of data.

Another area to look into is the audio settings of your chosen streaming app. Volume control and equalizer settings can be useful if your music sounds tinny, strangely thin, or bass-heavy.

Apple Music has its own equalizer settings, which you can access via Settings > Applications > Music > EQ. You may have already chosen a preset; if so, turn off the EQ and listen again to see how it compares. A preset that works well with headphones probably won’t sound the same when listening to music through a car’s speaker system.

Apple Music also has a Sound Check mode, which is a normalization feature that automatically adjusts the playback volume. If a song is too quiet or too loud, Sound Check will attempt to equalize the volume based on its own measurement of perceived loudness. You can set this by pressing Settings > Applications > Music and switch Sound check on or off. Other music apps may have their own equalizer or volume normalization settings that you will also need to check.

After each change you make, it’s best to immediately check the impact by listening to your music again. You don’t want to compare after changing several different options because you won’t be able to accurately compare it to the original settings you used and, if necessary, revert them back to them as easily.

If CarPlay generally sounds fine but suddenly loses bass, volume, or clarity, a strange audio attenuation bug may be the cause. CarPlay has to lower the volume whenever Siri or your maps app speaks, and people have reported that the music can sometimes get stuck in this state afterward.

A common workaround, mentioned in this long-running Reddit thread over the past few years, suggests a workaround. Try activating Siri using the steering wheel control, then immediately press the button again to deactivate it. The thread includes reports from Mazda, Porsche, Subaru, Ford, Toyota and other owners suggesting that this has restored their music to normal.

Other bugs may also occur; In these cases, it’s worth removing your device and re-pairing it if Apple CarPlay isn’t working properly. A new connection will often reset any conflicting settings and restore normal operation. You can do this at Settings > General > CarPlayby selecting your car, then pressing Forget this car.

If you want the best audio quality in your car, you will need the highest quality audio source. A wired CarPlay connection works best, but you’ll still need to switch to lossless playback in Apple Music or Spotify to eliminate the quality-reducing compression. Avoid streaming variability by downloading files in lossless format before you go. Any audio settings you have configured, especially custom equalizers in streaming apps, are worth double-checking.

There is, however, a limit to what you can achieve with just a few changes to your settings. Your speaker setup, including your amplifier, will have a big impact on quality. The acoustics of your car while you drive also have a major effect. Experimentation is your best bet here: make one change at a time and listen carefully to see if it makes a big enough difference.