Track Effects in 10.4.2 not working

[DCPImages]

I am sure you might have looked at this, but just in case... I have run into ‘problems’ in the past using tracks and not having things working as they should and I finally worked out that I had one clip overlaid over another on the same track and this was invisible to me until I pulled the top one out of the way and then things worked as they should? I am still not sure how the overlying track got there, but it was not my intention to create one. I suspect at some point I accidentally had 2 inputs for the track and the overlaying clip was created automatically.
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