Previous articleMissing sound on Xiaomi Redmi Note 4: what to do and how to return audio

The problem with the missing sound on Xiaomi Redmi Note 4 is one of the most common complaints users, especially after updates MIUI Unlike current models, where the audio system is duplicated, this 2017 model often has systemic problems ranging from a simple driver failure to physical damage to the audio codec. If the sound is suddenly gone, without falling or getting moisture, 80% of the time the software is to blame.

In this article, we will look at all possible causes, from trivial (switched off sound in settings) to complex (motherboard malfunction), and give step-by-step instructions with illustrations and diagnostic commands. 4 (codenamed mido, where the sound often “flyes” after being firmwareed through Fastboot due to version incompatibility audio_policy.conf. If you are not a technical specialist – do not worry: we have painted solutions from simple to complex, so that even a beginner can restore sound without contacting the service.

1. Checking the basic settings: what could turn off the sound

Before you sin on hardware malfunctions, make sure that the problem does not lie in the banal settings.Redmi Note 4 on the MIUI It has several “pitfalls” that make the sound seem absent:

• 🔇 Do Not Disturb Mode: Activated accidentally through the notification panel or on schedule. check the bell icon in the top curtain.
• 🎵 Disabled media notifications: in MIUI The sound can be “extinguished” for specific applications (for example, YouTube or Spotify).
• 🔊 Hardware buttons: Redmi Note 4 often sticks the volume button, physically transferring it to the position "0».
• 📱 On the plane profile: disables all wireless modules, which can block the sound in Bluetooth headphones.

How to check:

1. Pull the notification curtain down and make sure the Do Not Disturb icon (moon or crossed bell) is not active.
2. Press the volume button for 3 seconds - an adjustment slider should appear.
3. Go to Settings. → Sound and vibration → Volume and check if levels for multimedia, alarm clock and notifications have dropped.
4. Connect wired headphones – if there is sound in them, the problem is in the speaker or 3.5 mm connector.

If the sound is gone after connecting a Bluetooth device (such as headphones or speakers), try resetting your Bluetooth settings:

Settings → Bluetooth → Press three dots (⋮) → Reset settings

2. Software failures: reboot, cache and reset settings

More than 60 percent of Redmi Note 4 loss of audio is due to software errors.

Forced reset

Sound drivers freeze, and it's a common problem after a long time on the phone.

1. Press the power button for 10-15 seconds until the screen goes out.
2. Wait 30 seconds and turn the phone on again.

Clearing the cache and data of the “Phone” application

Sometimes the sound goes missing because of a failure in the com.android.phone system app.

1. Go to Settings → Applications → Application Management.
2. Find “Phone” (or com.android.phone) and select “Storage”.

Reset all settings (without loss of data)

If previous methods have not helped, do a soft reset:

1. Go to Settings → Additional → Resetting settings.
2. Select “Reset all settings”** (not to be confused with “Reset to factory”!).
3. Confirm the action. The phone will restart, but the files and applications will remain.

Safe mode will help determine if a third-party app is to blame.

1. Press the power button until the shutdown menu appears.
2. Press the “Switch off” finger and hold it until the suggestion to go to safe mode appears.

If sound appears in safe mode, remove the applications installed before the problem occurs (especially Magisk modules or custom firmware).

3. Update MIUI and driver recovery

Redmi Note 4 is especially sensitive to versions MIUI. If the sound is gone after the update, the problem may be in the:

• 🔄 Incompatibility audio_policy.conf (sound-file).
• 🔊 Damaged drivers qcom_audio.ko (sound-processing).
• 📱 Conflict with Magisk modules (if you have root).

Decisions:

Update to the last stable MIUI

Check the current version in Settings → The phone. → Version. MIUI. If she's older. MIUI 12.5, upgrade:

1. Download the latest firmware for mido from the official Xiaomi website.
2. Move the file to the root of the phone’s memory.
3. Go to Settings. → The phone. → Updating the system → Three points (⋮) → Select a firmware file.

3.2. Recovery audio_policy.conf

If the sound disappeared after running through Fastboot, it's likely that the configuration file was sent to recover it:

1. Download the original audio_policy.conf mido.
2. Use Root Explorer or ADB, to replace the file along the way: /vendor/etc/audio_policy.conf
3. You have rights 644 (rw-r)--r--).
4. Reboot the phone.

3.3. flashing through MiFlash (last chance)

If the sound never came, you'll have to stitch the phone in mode. EDL:

1. Download the full firmware for your model.
2. Install the MiFlash Tool.
3. Transfer the phone to Fastboot mode (clamp Volume down + Power).
4. Connect to your PC and swipe with the “Clean All” option** (Warning: Delete all data!).

💡

Before you use MiFlash, disable the antivirus – it can block Qualcomm drivers.

Hardware problems: speaker, 3.5 mm connector, plume

If the software methods didn't work, the problem is probably hardware. Redmi Note 4 most often fails:

• 🔊 Lower speaker (clogged with dust or contact leaves).
• 🎧 3.5 mm audio connector (oxidation of contacts or break of tracks).
• 🔌 Audio codec plume (remixed when the cover is opened frequently).
• 🔋 Qualcomm Audio Codec WCD9335 (overheating).

How to diagnose:

For self-checking:

1. Blow the speaker with compressed air (not your mouth!) Often the sound is lost due to accumulated dust.
2. Rock the 3.5mm connector – if the sound appears/disappears, the problem is contacts.
3. Press the bottom of the body near the speaker, and if you hear a sound, the plume will move away.

💡

If the phone doesn’t detect the headphones when you connect (there is no headphone icon in the status bar), the problem is precisely the 3.5mm connector or audio codec.

5. Diagnostics through engineering menu and test codes

Hidden tests will help you determine exactly where the sound is missing – at the software or hardware level.

Engineering menu (MTK)

Although the Redmi Note 4 runs on the Qualcomm Snapdragon 625, it has a hidden menu for audio testing:

1. Open the Phone app and enter the code: ##4636###
2. Run the Speaker, Headset and Mic tests**.

Test codes for diagnostics

Enter these codes in the Phone app**:

• #36446337## - Vibration and audio test

If there is sound in the tests, but it is not in the system, the problem is: MIUI If there's no sound in the tests, there's a hardware malfunction.

6 Repair in the service: when nothing can help

If you've exhausted all the options and the sound hasn't come, you should go to the service.

• 🔧 Replacement of speaker - from 800 to 1,500 ₽ (depending on the originality of the detail).
• 🔌 Ringing / replacement of audio connector 3.5 mm - 1000-2000 ₽.
• 🔊 Replacement of Qualcomm audio codec WCD9335 — 2 500–4 000 ₽ (demand BGA-soldering iron).
• 📱 Salting of the plume or contacts on the motherboard – 1,500–3,000 ₽.

Should I repair it? Given that the Redmi Note 4 is now in the secondary market. ~3 000–5 000 ₽, repairs are justified only if:

• 💰 The cost of repairs does not exceed 30-40% of the price of the phone.
• 🔄 You have a backup SIM card or phone for the time of repair.
• 📱 The phone is used as a "spare" or for specific tasks (e.g., a "spare" phone, GPS-logger).

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Before submitting to the service, make a backup copy through Settings → Additionally. → Backup or Xiaomi Cloud.Some services reset the phone to factory settings.

7. Alternative Solutions: How to Live Without Sound

If repair is not feasible, but the phone is still needed, here are the temporary solutions:

• 🎧 Bluetooth headphones: connect wireless headphones – sound will go through them.
• 🔊 External speaker: use USB-OTG + active column (e.g., active column, JBL Go).
• 📱 Sound forwarding: With the SoundAbout app (requires root), you can redirect the sound to Bluetooth or USB-device.
• 💬 Vibration and subtitles: include vibratory response and subtitles in the video (on YouTube: Settings) → Subtitles → On.).

For calls:

1. Activate “Call Vibration”** in Settings → Sound and vibration.

FAQ: Frequent questions about the sound on the Redmi Note 4