Using the call waiting function
If you receive a call while another call is already in progress, you can place the current call (call A) on hold and switch to the new call (call B).
Some of mobile phones may not be compatible with these functions.
Press the call button once during the call.
This places the current call (call A) on hold and switches to the new call (call B).
When the new call (call B) ends, the headphones return to the call that is on hold (call A).
To return to the call that is on hold (call A)
Press and hold the call button for approximately 3 seconds during the call (call B).
This places the current call (call B) on hold and switches to the call that is on hold (call A).