A:AnswerHi There,
the filter is to eliminate interference on your phone line, I do not know if this will eliminate the noise from the MagicJack product. Sorry cannot answer your question, perhaps, best to try it!
Have a great day!
A:AnswerYes. I used one on a splitter, one line for the phone, one line for the computer (DSL). Of course I put it on the side of the splitter I used for the phone.