Slide time marker changes when scrolling slides

I have the slide time marker on slide 17 (out of 50 slides).  I scroll the horizontal scroll bar and the time marker doesn't follow slide 17 - it remains at the physical position which isn't the actual time of slide 17.  Say the start of slide 17 is at 11:18 and I move the horizontal scroll bar to the say to look at slide 26 the time marker is now sitting at the start of slide 26 and the time shown above (in the bottom of the preview window) still shows 11:18.  This implies that the timing of the slides has changed.  The time marker should stay locked on slide 17 and not move relative to the slides.  Does anyone else have an issue with this?