The 3D transmitters are usually located in the right bottom area of the TV. Physical objects placed near or in this area, such as a center speaker of the theater system, may cause some interruption or loss of sync between TV and 3D glasses.
The 3D glasses receive an IR signal from the 3D transmitter, so there is a chance they could be affected by other IR devices and lose the 3D sync. It depends on a combination of location and distance between the devices and the specifications of the other IR device being used (IR transmission frequency, etc.).
If interference does occur, if possible, move the affected IR transmitter or device away from the 3D TV. In particular, make sure the path between the 3D TV and the 3D glasses is clear. If moving the other transmitter is not an option, turn off the 3D mode on the television when using the other IR device.
For example, IR communication could be interrupted if an IR wireless headphone transmitter, heater, or direct sunlight is positioned between the 3D glasses and the 3D transmitter. If this happens, the IR headphone transmitter or heater should be moved away from the 3D transmitter and/or moved away from the direct sunlight. Another option is to turn off 3D mode on the television when using those devices.