You may have to switch the tip an ring line. I at one time was installing residential cable, phone, and internet, and If they are running the same gear which is likely, then on certain systems it would make a difference if the tip, and ring lines running off the cable modem where just jumped from the modem to the other system they would be reversed, so you would have to run to a phone jack , and reverse the two wires, or by any other method flip the tip and ring. it never seemed to be a problem with a newer phone set, but older equipment, and for sure on alarm systems you had to get it right or there would be problems. No guarantee, but it's worth a try. good luck, and you should never need any other module or electronics to make the connection work. They hooked up to pbx systems on a regular basis. Hope this helps... Tom...
