# Fix audio problems

## What Blink audio is

Blink carries the remote computer's **system sound** to you: whatever the computer is playing through its default output, such as alerts, videos or a ringing phone app. It does not carry a microphone, and it does not send your sound to the customer. It is not a voice call.

## Symptoms

- The audio button in the viewer shows **Muted**, **No audio** or **Audio not allowed**.
- The button shows **Audio on**, but you hear nothing.
- The sound is thin, tinny or choppy.

## No sound at all

1. **Unmute.** Browsers do not allow pages to play sound on their own, so the viewer starts muted. Your first click or key press in the viewer unmutes it, unless you muted it yourself. Click the audio button to switch between **Audio on** and **Muted**. Your choice is remembered in this browser.
2. **Check that something is playing.** You only hear sound while the remote computer is actually playing something. Ask the customer to play a short sound.
3. **No audio.** The remote computer is not sending sound. The session details in **Sessions** show **Audio** under **Remote computer**. If it says **no**, Blink could not capture the computer's sound when the session started, for example because it had no working output device. Ask the customer to check that their speakers or headphones work, then start a new session.
4. **Audio not allowed** (Mac only). The customer has not allowed **Screen & System Audio Recording**, which covers sound as well as the screen. See [Fix missing Mac permissions](/troubleshooting/mac-permissions/). Once it is allowed, sound starts after Blink restarts.
5. **Not included in your plan.** If the button is greyed out on **No audio** and its tooltip says **Not included in your plan: remote audio**, your plan does not include **Remote audio**. See [Understand your plan and its limits](/configure/plans-and-limits/#when-something-is-not-in-your-plan).
6. **Check your own side.** Make sure your computer's volume is up, the browser tab is not muted, and your speakers or headset are the selected output.

If the customer changes their default sound output during the session (for example by plugging in a headset), Blink switches to the new device by itself.

## Thin, tinny or choppy sound

1. On a weak connection, Blink lowers the audio quality along with the video, down to mono. Improving the connection improves the sound too. See [Fix slow or choppy video](/troubleshooting/slow-video/).
2. Some laptops apply sound "enhancements" to their built-in speakers that cut the low tones. Blink hears the sound as the computer processes it, so you hear the same thin sound. Turning off the enhancements in the customer's Windows sound settings for that output device can help.

## When to contact IZT

Contact [IZT](https://izt.app) if the session details say **Audio: yes**, the customer can hear sound locally, and you still hear nothing with the audio button on **Audio on**. Send the session id and the session log. See [Collect logs for IZT support](/troubleshooting/collect-logs/).