Unable to Reduce Edit Page Track Height

So I suddenly seem to have a problem with the track height of only the first track (V1) as you can see in the attachment. I've tried reducing the track height, but all it does is reduce the height of the clips, but doesn't reduce the vertical height of the track between the top of the Audio Track and the bottom of the V1 clips ?
This is strange as it has been ok before, but when I tried doing a magic mask track in the colour page, then went back to the Edit page, I suddenly saw this.
This is strange as it has been ok before, but when I tried doing a magic mask track in the colour page, then went back to the Edit page, I suddenly saw this.