There are several possible reasons. Below are the steps to solve the problem.
Sound comes only from one side of Philips SHB4385 headphones
Published on 2018-03-28
You are in a call
When you are in a call, it is normal that sounds comes only from the right earpiece. The microphone is also located on the right earpiece.
The earpiece is out of battery
Place both earpieces in the charging case and charge them.
The right and left earpieces are disconnected from each other
- Turn off both earpieces.
- Press and hold the multi-function buttons on both earpieces for approximately 3 seconds. This will turn the earpieces on and connect the two earpieces.
- Reconnect the headset to your Bluetooth device.
The headset is connected to more than one Bluetooth device
- Switch off the Bluetooth function of all connected devices.
- Turn off both earpieces.
- Press and hold the multi-function buttons on both earpieces for approximately 3 seconds.
- Reconnect the headset to your Bluetooth device.
Note that the headset is designed for connecting to only one Bluetooth device at a time. When you reconnect the headset to your Bluetooth device, make sure the Bluetooth function of any other previously paired/connected devices are off.
If the above does not help….
Factory reset the headset.