This sort of thing happens all the time with many X10 devices. Most sites say that the most likely reason is that one of your other electrical devices (e.g. a TV) is putting noise into the power lines and that this is sometimes solved by adding a noise filter to this device.
The first logical place to start is to plug in the module to different outlets and test it to see if you can get it working anywhere first. If you can, then you probably do have a noise or transmission problem. Step 2 is to attempt to identify which of your home appliances or devices are causing the problem. The new TV you mentioned is a good candidate for signal transmission problems and/or noise. Try unplugging it and see if the X-10 signals get through. If they do then you probably need an inexpensive noise filter for your TV. If they do not, then try to test other possible culprits in your home such as a PC, microwave, furnace and especially fluorescent lights such as those on some ceiling fans. Try some of these tests, if you need more help let me know.
Please read the following: Unsolicited commercial advertisements are absolutely not permitted on this forum. Other private buy & sell messages should be posted to our Marketplace. For information on how to advertise your service or product click here. Remote Central reserves the right to remove or modify any post that is deemed inappropriate.