Text changes size mid-clip

Hi all,

During replay the occasional text layer/layers 'changes size' mid clip. The size in the inspector does not change though, just on screen during playback. I thought it may be because it hadn't rendered fully, or perhaps it was just a playback glitch within the program but the size change does occur after output. It is most peculiar!

Sometimes it happens before a dissolve or just after, sometimes it is near a blade cut, sometimes in the middle of clip.

Not sure if pix below will help clarify what is happening but worth a try. Pic 1 is where it should be, Pic 2 the text has become smaller and thinner. Is there anyway I can upload a video of the playback?

Anybody else come across this?

Many thanks

Gill