I have a LAN connection at home. I have a problem of recieving radio signals on my computer. My speaker is an in-built one.When I unplug my lan cable the signal is stopped. When I plug it in I recieve the radio signals. Can you help me out???
From your replies so far I'd have to guess there's a problem with sound circuitry on the motherboard.
But your answer is slightly ambiguous as to whether you can hear wireless thru the headphones when plugged into the CPU (by which I assume you mean motherboard). And what happens if you mute the mike input in the mixer ?
My point being that these issues mostly arise at the amplifier stage due to poor design, bad solder joints or poor screening -- very common for example with cheap amplified external PC speakers that are in common use. And mike input is the most sensistive so if that's not perfect it can cause problems (that can be solved by muting in the mixer).
When you say LAN -- do you mean literally a local connection to other computers in the building or do you mean the internet feed (WAN) ? Because connecting to the phone system or cable feed may have a bearing on the issue.
This sort of problem is very hard to nail down. There was a thread running for about a year on this before. It comes down to badly designed or badly made audio circuits.
Have another look at this from my earlier post : "your answer is slightly ambiguous as to whether you can hear wireless thru the headphones when plugged into the CPU (by which I assume you mean motherboard)."
If you can't hear any wireless interference when using headphone DIRECTLY plugged into the motherboard audio output, the problem may lie with the amplifier/speaker unit you are using.
A likely solution then is to try adding some new amplified speakers plugged into the outlet you just tested.
Make sure the network cable feeding your computer has a ferrite choke on it -- this is easily identifiable as a lump in the cable (similar ones are used on monitor cables and some USB cables.
A choke may help reduce the spurious radio signal. Beyond that, you probably need more technical help. In most countries there is an authority responsible for governing the airwaves (in US the FCC) and their technical types would be expert at this type of problem.
Have a look at their website or try calling. I had problems like this some years ago with local taxicab firm radio interfering with my hifi -- and the UK authority guys were slightly helpful.