Below are our frequently asked questions. If you don't find the solution to your problems, feel free to contact our customer service team here.

A. The CPR Call Blocker will work on all standard domestic telephone lines from all the main US telephone providers.

A. The CPR Call Blocker uses only the power from your telephone line which is of no cost to you!

A. The CPR Call Blocker uses the power from your telephone line so there would be no interference.

A. The Nuisance Call Blocker will work with a wide range of telephone equipment - cordless DECT phones, cordless analogue phones and text message phones.

A. Yes it will work with all major VOIP providers such as Magic Jack, Fios etc However it will not work with ooma.

A. No, it won’t. We have contacted all the major suppliers of these panic alarm devices and all suppliers have said that it should be compatible. All they would request is that when you purchase one, you give them a call to advise them that you are connecting a call blocker together with it.

A. You can manually program the Blocker if you wish, but the CPR 'Block Now' Button is the easiest way of blocking an unwanted number.

A. The CPR Call Blocker does not interfere with the functionality of answering machines.

A. It will work on Hybrid PBX systems with an analog handset - email us for more information.

A.Yes the CPR Call Blocker will work with Two line phone systems but you will require two Call Blockers and a Steren 4-Conductor 2-Line Split Adapter, more information can be found here - http://cprcallblockerforum.com/index.php?threads/how-to-add-two-cpr-call-blockers-to-a-two-line-phone-system-in-the-u-s-a.2473/ .

A. Yes you can but problems can arise, If you wish to have several phones around the house it is best to use a DECT phone with multiple cordless handsets.

A. No, only if you manually program the unit to block all international calls.

A. No, only if you manually program the unit to block all Private calls.

A. Depending on which version, the Call Blocker can have up to 5000 numbers pre-programmed and the ability to block a further 1500 numbers.

A. This is most likely down to intermittent caller id caused by a faulty DSL filter, removed the filter to see if this fixes the issue and replace if necessary. this problem can also be down to having too many devices attached to your line, try disconnecting some equipment to see if it resolves the issue.

A. Yes, all new stock from August 2015 now fully works with ooma.

A. Yes the CPR Call Blocker has the ability to work World Wide, but if you have a weak caller id signal you may have to setup the call blocker as the image below.

A. The CPR Call Blocker will work happily alongside your DSL connection - just unplug your telephone and plug into Call Blocker.