We recently moved into a new office that was built out from a basic concrete room. We had an electrician instal our telephone wires and then had a technician from our telephone service provider connect the jacks to our lines.

Everything is working fine with the exception of one jack. When we have a phone/polycom plugged into this jack, it will work one day but not the next (i.e. dial tone today, dead air the next).

The phone line itself is fed to multiple jacks and works fine on the other outlets.

On days when we cannot get a dial tone on this particular jack, we have tried plugging in different telephone units and have also tried replacing the cord that connects the phone to the jack. These actions make no difference.

As is always the case, when we have a technician come out to look at it, the jack will work fine and then we get charged for a call out.

We aren't using any special office phone system (i.e. Norstar, etc). We have three regular telephone lines fed to multiple jacks in the office with a separate telephone/conference phone plugged into each.

Any possible suggestions would be appreciated!

Not knowing exactly what sort of jack you have (the type with screw lugs or punchdown)... but look at the jack where you plug the phone into it... do all the pins look straight and even and at the same level? Or are they uneven with one or more much lower than the others? If everything looks uniform and even you have to check that the screws are tight if it's the screw type... or if it's the punchdown type that its fully and properly punched down... you won't have the correct tool for that however or know what looks good or bad unless you work with them daily if it's that type.

Hi Smoothy,

Thank you for your response! It looks like all the pins are even - there are certainly none that are at a different level. When I peer inside the jack though, some pins look darker than others. This may be normal.

Is there anyway for me to determine whether the jack is a punchdown or screw type? As with the rest of our outlets, the jack has both a telephone and data connector. The only visible screws on the plate are the two (top and bottom) that serve only to fix the plate to the wall (or box). I took a quick look on Google images and it looks like the plates for screw types show the screws that fix the plate to the box and then another set closer to the centre of the plate. Is this correct? If so, I would presume our jack is a punchdown type. Also, the wires are connected to a 'bix block' panel - does this help us determine the type of jack?

Many thanks!

A Bix block is the punchdown type. That's going to be beyond your ability to do anything with. It takes a trained eye to spot a bad punch form a good one. You won't have the proper tool anyway.

I'd have the jack replaced. You have to trim back the wires when you replace a jack and that would eliminate a possible break or bad punch (as well as a flakey jack). Because you have to pay someone to come out, you will eliminate several possibilities at one time... minimizing your cost. If you had the tools and knew what to do with them... I would break that down to a few more steps. WIth replacing the jack itself as a final move.

As far as the pins... because of what you described after I asked... it appears they have suffered no damage. I wouldn't worry about the uneven discolorations there. THey are brass and not gold plated (those would have been premium quality jacks if they were)... brass will tarnish.

Virtually all phone jacks used in business environments these days are punch down, so it takes a special tool to re-seat the connections on the rear. If you're getting an intermittent connection the problem coud be elsewhere - for example, in the telephone closet where the extension is connected to the telephone company lines (or to your PBX if you have one). If the problem persists I'd have the technician install a new jack.