Help Camera re-focusing during Video Recording

[thicks56]

I've just noticed over the past week that when recording videos my camera in and out of focus twice about a second apart every time I pan the camera,

Has anyone else experienced this?

Im pretty sure its not a post JB issue but I have checked over my old videos and whilst there obviously is some re-focusing it isnt noticeable in the old videos unless your really looking hard at the video.

I would post a video but im not really sure how

Thanks in advance for any advice