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Headphones Aren’t Charging.
You plug in your micro-USB cable, and the headphones do not spring to life.
Ensure that your cable is firmly plugged into your headphones and power source. If there is a proper connection, there should be a red light illuminated near the power button on the left ear cup.
If your headphones are plugged in but there is no red light on your left ear cup, you may have a faulty cable and should consider buying a new one.
It is possible that the battery is not working properly. In this case you can follow our guide here to replace the battery or to check the connections between the battery and the device.
Broken Charging Port
If other solutions do not work, your charging port might be broken. To fix this you can follow the replacement guide found here.
Bad Sound Quality
The audio coming from the headphones is muffled or is a static-like sound.
Audio Output is Not Working For Current Volume
Try turning the volume down significantly. It is not uncommon for music to be played at volume levels at which the headphones can not manage.
You could also try turning the volume up significantly. The audio could be playing at such a low volume that the sound quality seems to be low.
Bluetooth Connection Interference
Many things can interfere with a Bluetooth connection and this interference can result in bad audio quality. One quick fix to this problem is to bring the headphones and Bluetooth devices as close as possible, avoiding any obstacles that could be interfering with the connection.
If this is not possible or does not fix the problem, try keeping the headphones away from microwaves, Wi-Fi devices, televisions, or anything emitting waves (radio, microwave, ect.) that could interfere with the Bluetooth connection.
Problem With Bluetooth Device
It is possible that the root of the problem could be the device that the headphones are connected to, not the headphones themselves. Before you look into complicated solutions and replacements, make sure to check the audio coming from your Bluetooth device through another audio output. This is so you can be positive that the problem is coming from the headphones and not your Bluetooth device.
Faulty or Broken Speakers
If all other possible solutions fail to solve this problem, it is likely that one or both of the speakers inside the headphones are “blown out” or simply broken. To fix this you must replace your speakers; however, this can be very difficult and can lead to the device being irreversibly damaged.
Audio Connection Cuts In and Out
The headphones are paired but the Audio is cutting in and out.
The Device is Out of Range
Although the phone may still display that it is paired with the headphones, there is an operational range that audio can be clearly transmitted. Bluetooth has an optimal connection range up to 30 ft (10 meters). If the problem only persists while the phone is a fair distance away from the headphones, this could imply that you are approaching the upper range of the Bluetooth connection. This range can also very depending on the objects/materials in between the connection
Various emitters of Radio Frequency (RF) signals may alter and distort the connection between the phone and headphones. Microwave ovens, TV remotes, cordless phones, baby monitors and some car alarms among other things all generate RF interference. Make sure your device is isolated from these other devices before determining that this is the issue.
The wires within your headset may be damaged or connected improperly. To fix this, you will need to replace your current motherboard. Please follow the replacement guide found here to help guide you through this process.
Difficulty With Bluetooth Pairing
There are problems with Bluetooth pairing or the Bluetooth connection.
Device Not Pairing
Ensure that Bluetooth is enabled on the device you are trying to pair.
Hold the power button for 7 seconds or more to enter pairing mode, and make sure your headset and Bluetooth device are within 3 feet of each other during the pairing process. If difficulty arises with the connection of headphones and device, delete the pairing information from the device, and pair again.
Bluetooth Disconnecting While Connected
If the headphones seem to disconnect while in use, check if the headphones are connecting to another Bluetooth device. To fix this, turn off Bluetooth capabilities from the device not in use.
Unable to Connect to a Device With One-Touch Connection (NFC)
Remove smartphone from its case and insure that the NFC function of the smartphone is set to on. If the headphones fail to connect, move the smartphone slowly on the N-Mark of the headset.
You cannot make a one touch connection while charging because the headset cannot be turned on. Additionally, a one-touch connection cannot be made while a headphone cable is connected to the input jack.
Broken NFC Chip
If other solutions do not solve this problem then it might be that your NFC chip is broken. To replace this, follow the replacement guide found here.
No Sound/Noise Cancelling
Audio is not coming from the headphones or the noise cancelling ability is not working.
Make sure that the batteries in the headphone are fully charged by pressing the power button once. 3 red blinks means it is fully charged, 1 red blink and it is low charge.
Make sure that the headphones are in range (30ft) of the connected device. Make sure that volume on both the device and the headphones are turned up. Check the Bluetooth configuration for the device is set to Sony WH-H900N h.ear on 2. If neither of these fix the issue, pair the headphones and the device again.
Try above steps and make sure that the noise cancelling button is turned on (indicator light is green next to NC/AMBIENT).
*Note that the noise cancelling function is for low frequency noises such as airplanes, trains, air-conditioning and not high frequencies such as human voices*
It is possible that the microphones that help operate the noise cancelling are broken. To replace these, follow our replacement guide found here.
If none of these solutions or diagnoses seem to help, check out Sony’s help guide.