Solution: This is a problem that customers have had with their Plantronics CS55 wireless headsets and other similar CS wireless models (e.g. CS70N, CS351N) and a simple fix is to make sure the compatibility dial, located to the left of the base, is properly set.  The indicator, set at 3 o’clock, normally points to #1 (that covers 90% of phones) on that dial but you may need to use one of the other 3 settings for optimum clarity.  It should never be set between numbers.  The right compatibility setting is crucial to the proper operation of your Plantronics CS55 wireless headset.  On occasion you or someone else in your office may bump the unit and not realize the the dial has been slightly turned.

The bottom of the base will have a white sticker starting with “B” for base.  This is followed by a letter representing the Month (A=January, B=February…) and a number representing the Year (6=2006).

The headset will be located under the ear cushion and follow the same letter/number combo as listed above.

1) Plug into a Cisco VOIP phone (the standard one you see everywhere)
2) Greatly amplify volume (so for example, if the call is very hard to hear even with phone’s volume blasting, headset would further amplify sound)
3) Has a mute button on board the headset
4) Cordless would rock but could live without it.

Answer:  If you have any of the 7940, 7960 or 7970 model Cisco phones, you can use just about any of the Plantronics wireless systems such as the CS55, CS70N, CS351N, CS361N, etc.  These wireless systems have a button for adjusting your listening volume and a mute button right on the the actual headset.  The wireless headset charger / base amplifier has independent controls for both your incoming and outgoing volume.

A: No, the Plantronics CS351N and CS361N are a much better choice for a rugged environment.