As with any piece of technology, you may encounter glitches on your journey with this Sennheiser Bluetooth headset. Luckily, they are usually minor and can be fixed with one of these resets below!

Sennheiser MB 660 General Reset
- Switch the Headset OFF. To do this, turn the earphones outward (so the headset is flat and can go back in its case) to turn it OFF. It will say “Power Off.”
- Press the Sound Effect Mode button for 4 seconds. This is the bottom button on the right side of the headset. Its location is shown in the first graphic at the bottom of the page, Section 2. (the inside of the headband will have R for right and L for left)
- NOTE: after holding the button down for 4 seconds it will not give us any light or say anything. To see if the reset worked we can try pairing the headset to the phone again
Headset still acting up? We have something else to try!
Clearing Previously Paired Devices
- Restart the headset by switching it off and on again. To do this, twist the headphones as shown in Section 1 of the first graphic below
- Press the Sound Effect Mode button for 4 seconds. This is the bottom button on the right side of the headset, as shown in Section 2 of the first graphic below. You will hear tones and a voice prompt that says “Phone _x_ Disconnected” (x= the name of the device, example Phone 1 or Phone 2) and “Pairing” and the LED lights on the headsets will flash white in sequence
- Press the Sound Effect Mode button again for 4 seconds until you hear tones and the voice prompt saying “Pairing List Cleared.” The LED lights will flash white in sequence. The headset is now permanently disconnected from all devices and will automatically enter pairing mode. See the second graphic for information on Step 3 in the pictures below


Headset STILL giving you problems? Give our Product Support team a call at 800-923-0018!