There's no need to re-pair the TC417 each time.
It will auto reconnect to the LAST paired headphone/receiver once you power on both devices and wait for 5-10 seconds. Otherwise, turn off and on both devices again.
For the 2nd headphones, they may auto reconnect to the TC417 after waiting 5-10s once power on. Otherwise, please manually enter BOTH devices into PAIRING MODE.