I suspect the cooling fan is burning/wearing out. Replaced the original bulb after 15 months of use. After the next 12 months similar noises and issues started again. Solution was to take off the cover for the lamp unit and drill 8 to 10 of 3/16 inch holes in the door to allow more cooling air to enter. Second lamp is 7 months or 50%older than original. Lamp not an issue. TV manual does not identify how to remove door at rear right hand side. opposite lamp door. Should fan need replacing too?

I think you have lost the fan. Check the installation and make sure the fan switch is activated. You must have a fan going or the bulb will actually burnout soon that is why the fail safe circits are shutting it down; to keep the lamp from burning up. Got to get the fan going.

Need to know the make and model of the microwave. Also what bulb it is. If this a halogen bulb, you must wear rubber gloves to change it. The oil in your skin with cause the bulb to break when it heats up.

the bearings/bushings are wearing out. It happens to these fans. Best bet is keep it clean while you can and it still works and keep an eye on it. When it stops working finally get it replaced. You can load a freeware app like http://www.almico.com/sfdownload.php speedfan to keep track of the temperature on your laptop. When it starts climbing too high get the fan replaced.

YOUR TV MUST NOT BE SUROUNDED BY BIG IMPOSSING OBJECTS YOU MUST HAVE AT LEAST 3 FEET FROM BACK WALL THE COOLING FANS MUST BE CLEANED OPEN BACK COVER AND CLEAN FANS IF LAMP STILL BURNES AFTER YOU MAY HAVE A BALLAST PROBLEM

Another possible source for the noise is the Color Wheel. It is spinning at a high rate and the noise will get louder as it wears out. You should be able to replace the part yourself. Take a look here first: http://www.fixya.com/support/t372149-samsung_hlp4663w_color_wheel_replacement

The fan can be replaced. It is very similar to some of the PC cooling fans. I've got the same problem (again) and will be replacing it soon. I will give you the fan specs once I remove my fan ( I think it is 4" 120VAC - will let you know when I repair mine).

We had a projector at our church that was hooked up to a light switch to turn it on or off and it kept burning the bulbs out. We had an expert come in and look over our situation and he said When you are finished with the projector let the fan keep blowing until the unit cools down. Ours had a switch for the bulb as well as one for the fan. We turned out the bulb and left the fan on for an extra ten to fifteen minutes. That let the bulb cool down gradually If you just cut the power the bulb over heats and will burn out. Yes turning on for a few minutes will burn it our quicker as well. Hope this helps.

I would suggest getting an electrician to check the current running through the wiring. I had installed a similar fan in my grandmother's house a couple of years ago and had the same problem. After a couple of months of constantly changing bulbs, I brought in an electrician to check the current and found that there was a short in the wire which kept causing just enough of a current surge to blow the bulbs.

There are several reasons for short lamp life. Inadequate ventilation or clogged cooling fans, a bad lamp driver or lamp ballast (they are the same) and the use of non-original Sony lamps, as the aftermarket replacements are known problem causers. Remember too that the number of times the lamp is turned on and off is a BIG factor in how long the lamp will last.

Since the noise started with the new stand, I would suspect vibration as the noise. Did you attach the new stand to the plasma with screws? If the stand is not the issue, then, a fan inside could be making the noise. I have found the flex cables from various boards inside the set causing strange noises. Touch the back of the set and see if the noise goes away or changes in specific areas. When Plasma Panels are set in a corner, they seem to make a louder noise than usual. It could be the panel as well. If the set is one month old and bought from a retail store, then, it should be under warranty and a servicer could be called. Let me know what you found out.