Location of the microphone on Xiaomi Redmi 4X: the complete guide

Finding the sound recording element in a smartphone case is often a daunting task, especially if you’ve never experienced a Xiaomi repair. Redmi 4X owners often wonder about the exact location of this component when faced with communication or video recording problems. Understanding the design of the device is the first step to successfully restoring its functionality.

In this article, we’ll take a closer look at where the microphone is on your board, how to get to it, and why it might stop working. The main conversational microphone in Xiaomi Redmi 4X is located on the bottom sub-board, right next to the USB charging connector, a standard engineering solution for the budget segment, allowing you to optimize the space inside the case.

Not to be confused with the secondary noise suppressor sensor, which is hidden at the top of the case. If you're planning a self-repair or just want to understand the cause of the quiet sound, you'll need to carefully study the circuitry of the device. We'll look at all the nuances so you can confidently act in any situation.

Design features of the Redmi 4X audio system

Xiaomi Redmi 4X (model number MCE16) is equipped with a classic acoustic system for its time. Engineers have placed sound recording components at two diametrically opposite points in the case, which allows you to implement a basic noise reduction function, cutting off background noise during a conversation.

The main microphone you use 99% of the time (calls, voice recorders, video recordings) is integrated into the bottom module, which is a compact electronic component soldered to a circuit board, and the sensitivity of the cell is directly dependent on the quality of soldering and the absence of contamination in the protective grid.

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Before starting any dismantling work, be sure to back up important data, as accidental damage to the plume can lead to loss of communication with the motherboard.

The second, less visible microphone, is at the top of the device, and its primary task is to analyze the surrounding noise and transmit the data to the processor for filtering, and if this component fails, the interlocutor may complain of extraneous sounds or echoes, although the main voice will be heard normally.

Exact location of the main microphone

If you're wondering where the mic of the Xiaomi Redmi 4x is physically, you're going to look at the bottom end of the smartphone, and if you take off the back cover and remove the battery, you'll see the charging connector, and that's where, under a special protective metal or plastic grid, the component is hiding.

Visually, it looks like a tiny black or silver piece, round or oval, with a small hole in the middle. This hole should match perfectly with the cutout in the phone case. The shifting of the board or the deformation of the case after a fall can cause the hole to stop matching the grid, which will dramatically reduce the volume.

• 🔍 Bottom edge: The sound intake hole is located to the right or left of the Micro-USB connector, closed by a shallow grid.
• 🔌 Sub-board: The electronic component itself is soldered on a separate board, which is connected to the motherboard by a plume.
• 🛡️ Protection: On top, the component is covered with a porous gasket, preventing dust from entering directly into the membrane.

It is important to note that in some board revisions, the location of the component may vary slightly, but always remains in the area of the lower third of the device, and access to it is possible only after the body has been completely disassembled, since it is under the main elements of the structure.

Location of the second (noise-suppressing) microphone

Many users forget that there is a second recording element that plays a critical role as a communication element: on the Redmi 4X, it is located at the top of the smartphone, which is more difficult to find because it is often hidden under decorative elements or integrated into the button control board.

Usually, the hole in this microphone is on the top end, next to the headphone jack 3.5 mm. In some versions, it can be hidden under the screen frame. The noise reduction function works only when both microphones are working and transmitting correct data.

If you notice that you can't hear you when you're on speakerphone, or that you can hear your voice from a barrel, the problem may be in the top sensor, which is less likely to be contaminated with dust or moisture, but it's also possible when you're using your phone in dusty environments.

Disassembly instructions for accessing the microphone

To diagnose or replace the component, you will need to disassemble the device. Xiaomi Redmi 4X has a relatively simple design, but requires care. The presence of a suction cup and a set of screwdrivers is mandatory for safe work.

First, heat the perimeter of the back cover with a hair dryer or put the phone on a warm surface to soften the glue. Then, with a suction cup, lift the lid and walk around the perimeter with a plastic map. Be careful with the fingerprint scanner plume if it is glued to the lid.

The algorithm of actions is as follows:

1. Unscrew all visible screws holding the plastic frame of the case.
2. Remove the frame by snapping plastic latches around the perimeter.
3. Disconnect the battery and display plumes from the motherboard.
4. Remove the motherboard and the lower sub-board, where the main microphone is located.

Once the lower board is removed, you'll have full access to the charging jack and microphone, visual inspection will detect oxides, dirt or mechanical damage, and often simple cleaning with alcohol restores normal operation.

⚠️ Warning: When you turn off the plumes, be extremely careful. Close the connector contacts under voltage can disable the power controller or audio codec on the motherboard.

Diagnosis of malfunctions and symptom table

Before you start soldering or replacing, you need to diagnose the problem accurately. It's not always a quiet sound that means a microphone breaks. It's often a software failure or contamination of the external holes. Diagnosis saves time and money.

Use the standard Dictator app to check. Record the sound in a quiet room and in a noisy room. Compare the result to the reference. If the recording is intermittent or contains cracking, the hardware problem is, if the sound is just quiet, the grid may have clogged.

If the problem persists after cleaning and reconnecting the plumes, the electronic component itself is likely to have failed, in which case it needs to be replaced. On the Redmi 4X, the entire bottom board is often changed as it is more reliable and easier than soldering small parts.

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In most cases (about 80%), the problem with quiet sound is solved by replacing the lower sub-board along with the charging connector, since the microphone is soldered into it.

Replacement of microphone and lower board

The replacement process requires the skills to work with soldering equipment if you only change the microphone itself. However, as mentioned above, for the Xiaomi Redmi 4X, a more rational solution is to replace the lower board in the assembly.

To replace the board, you need to unseal the old module from the plume or disconnect it if you use a connector. In this model, you often find the option of soldering the board to the main plume. The soldering temperature should not exceed 350 degrees so as not to damage the textolite.

When installing a new board, make sure the contact pads are clean and well-deserved. The board's fixation with screws must be reliable, but without dragging, so as not to split the textolite. After assembly, recheck the sound recording.

⚠️ Attention: Use of low-quality analog parts can cause extraneous noise or a new microphone to fail quickly. Choose trusted suppliers.

Frequently Asked Questions (FAQ)