Simple solution. We've tried the tape game, paper game, etc etc. This merely knocks down the overall IR into the target to produce a greater S/N ratio for the real commands to enter, also reduces overall range for the real codes unfortunately. The best answer I know of is the IR targets from Speakercraft which are truly plasma proof (as well as halogen and other stray IR noise producing products). The problem is mainly related to the plasmas producing in frequency IR noise which can also be reflected off of room walls and back into the IR target. The Seakercraft seems to solve this problem using some noise immunity circuitry that would appear to "learn" the noise and then reject it. The brighter the image on the plasma, the more the noise. Class A (Pro??) plasma products also seem to have the same problems as their class really only refers to the fact that they are allowed to emit more stray RF as they are to be used in commercial environments only (?), as compared to Class B types for residential use.