Find out what is the reason for the loud and low sound of the speaker

The output relay contacts are aged, leaving the output in a half-contact state. The sound of the audio suddenly becomes louder and then smaller, and you should check whether the audio signal output by the audio source is as loud as the left and right channels, and also check whether the audio cable is abnormal.

On the issue of abnormal noise, it is difficult for ordinary car owners to distinguish which ones are fault abnormal noises and which ones are reasonable abnormal noises. Only nearly 20% of the vehicles that went to the repair shop to detect abnormal noises really had problems. In the case of a turbocharged engine, there is a must be a difference between the sound and the sound of a naturally aspirated engine; Models with engine guards may also make noises due to friction; After some car owners come into contact with different cars, it is likely that due to their lack of understanding of mechanical knowledge, they mistake reasonable abnormal noise as a vehicle failure.

Therefore, learn to distinguish the abnormal noise of the car and avoid wasting time and energy.

The identification of car noise is limited, and it is difficult to use special instruments to measure the sound of the car, and the sound of the car can only be described and compared with the judgment of the sound in daily life. For example, the "rattle" sound caused by the dry friction of the bearing, and the "click" sound similar to the small hammer hitting the cement floor caused by the excessive valve clearance.

1. Correctly distinguish between normal and abnormal sounds.

The vibration of each mechanism in the work of the car will emit a variety of sounds, but the sound does not mean that the car is faulty, in order to avoid unnecessary disassembly, we must first distinguish between normal sound and abnormal noise. The normal vibration sound of each system component (such as the noise on the surface of the engine), the impact sound of the gear when shifting, the air intake sound and exhaust sound of using gas as the working source, and the gear meshing noise are all normal sounds. Abnormal noise (abnormal noise) can be divided into slight noise, general noise and malignant noise according to the impact on the performance of the car.

Slight noise, such as the flashover sound of high-voltage electric leakage, the slight loose sound of rolling bearings, etc., the general volume is small, the degree of wear of the parts is not large, and there is no significant change for a long time, and this kind of fault can still maintain the normal operation of the car without repair.

3. When diagnosing abnormal noise, attention should be paid to creating good auscultation conditions and trying to eliminate the interference of other noises, so as not to affect the accuracy of judgment.

It is best to consciously amplify or reduce the sound, that is, use a screw or other metal rod as a stestological instrument to contact the sound part to amplify the sound, or use a single cylinder fire cut-off to reduce the sound to meet the diagnostic needs. The auscultation site should be kept quiet to minimize human interference.

There are poor contact places in the power amplifier, and it is rare that the horn coil is a problem.

Master volume potentiometer, just change it.

Horn moisture: The car horn device generally has good sealing, but with the increase of service life and the increase of the number of times, it will inevitably lead to a decrease in its sealing.

The horn button is broken: If the horn button is pressed for a long time, it will also cause it to be damaged, and the damage of the button is also one of the factors that the horn does not sound.

Poor contact: The internal solenoid coil of some models.

The terminals are not connected by soldering, but by aluminum rivets, and if the insulating paint of the port is not properly treated, or the connection is not in place, this will lead to poor contact.

Horn circuit is broken: If the owner likes to honk the horn for a long time in the process of driving the vehicle, then this will cause the resistance of the horn's contact to be too large, which will cause the current of the horn circuit and the electromagnetic coil to weaken, and finally cause the car horn to have a hoarse sound, or no sound failure.

There are 3 possibilities for the volume to fluctuate:

1. The volume potentiometer is dirty and aging, resulting in poor contact, and this fault has a sudden feeling and is accompanied by a clattering noise when adjusting the volume, and the volume potentiometer can be replaced.

2. The output relay contact is aging, so that the output is in a semi-contact state, due to the excessive contact resistance, the output volume is weakened, and the change occurs under the influence of slight vibration or contact sparks.

3. For the power amplifier where the input signal is switched by the relay, the input contact may also be poor due to the poor quality of the input relay and the short life, similar to the second type. If the input is mechanically switched, it may also be caused by the poor contact of the input switch switch, and the input switch can be repeatedly toggled to see if there is any change.

Summary. Hello, there are 4 possibilities for the volume to be up and down: 1

The volume potentiometer is dirty and aging, resulting in poor contact, this fault has a sudden feeling and is accompanied by a clattering sound when adjusting the volume, and the volume potentiometer can be replaced2. The output relay contact is aging, so that the output is in a semi-contact state, due to the contact resistance is too large, the output volume is weakened, and the change occurs under the influence of slight vibration or contact sparks, and the judgment method is to knock the casing. Hope it helps.

Hello, there are 4 possibilities for the volume to be up and down: 1The volume of the potentiometer is dirty and aging, resulting in poor contact, this fault has a sudden feeling and is accompanied by a clattering noise when adjusting the volume of the model, and the volume potentiometer can be replaced2.

The contact of the output relay is aging, so that the output is in a semi-contact state, and the output volume is weakened due to the excessive contact resistance, and the change occurs under the influence of slight vibration or contact sparks, and the judgment method is to knock the casing. Hope it helps.

This is not the case.

Is there anything else?

If there is a murmur when turning the volume knob or the volume is loud and small, it can be solved by the following methods:1. Find this alcohol (95% industrial pure)2.

Disassemble speaker 3. Locate Volume Electric Parade Shaker 4. With clean chopsticks or a bamboo stick or something else, dip some alcohol into the potentiometer, 2-3 drops are enough, turn the potentiometer 5.

Restore the speaker.

Landlord, you try to reinstall your sound card driver.

Or the next driver wizard will ask him to update your sound card driver for you.

It's usually a sound card driver problem!

First, first confirm that the hardware is fine. If the speaker is fine, the sound card is fine, and if you've tested it on other machines and it's really good, then you can read on.

2. Make sure all the cables are exactly right. Then power on the speaker and turn on the volume switch.

3. Install the driver of the sound card correctly, if it is an onboard sound card, it is best to install the driver provided on the driver disk of the motherboard.

In fact, the computer does not make a sound, and many times it is because the sound card is not driven correctly. In general, after the sound card driver is installed, there will be a small speaker icon in the taskbar in the lower right corner. ）

Fourth, if you are sure that the driver is installed correctly, then take a look at the volume settings in the computer.

The specific method is to double-click the speaker icon in the taskbar, and check whether the volume is turned off to the minimum in the "Volume Control" and "Waveform" dialog box in the pop-up "Volume Control" and "Waveform".

If these two options are not available in the dialog box, click on the "Options" menu - select "Properties" - select "Volume Control" and "Waveform" in the "Show Volume Controls" and then set them correctly.

Note: Step 4 can only be set up after the driver for the sound card has been installed correctly.