Last night for the first time I used my XL1s with my Varizoom monitor hooked up. Today while logging and capturing I noticed that the saturation of my image was strobing, saturating and de-saturating on a regular pulse like wave. This is the first time I have noticed this using my XL1s so I am wondering is it an issue with the monitor or is there something wrong with the camera. Has anyone else encountered this problem?

What type of lighting, what was the period of the wave (the frequency of the variation) and what shutter speed?

While perhaps not the cause your problem, discharge lighting, such as fluorescent, can cause a periodic variations in the image exposure and color balance. This is cause by the slight difference between frame rate and power line frequency, especially at higher shutter speeds