the 7 was on ios 11 and the x is on whatever it was shipped with.What version of iOS was on the 7 when you backed up, and what version of iOS did you restore to (on the X)?
I deleted the old phone. ((Hmm, I was just trying to think through what would cause - assuming all - videos to be unplayable. My X needed the .1 update out of the box, which I performed before I restored - my previous phone was updated to the latest before I backed it up).
Maybe update both, do a fresh backup and restore.
[edit]
Doh! Yeah, what @rugmankc suggested
If it’s a restore from iCloud, it will take a while for everything to transfer.I backed up my 7 on Friday, then restored my new x from backup (icloud). all my videos are showing up but none will play. just shows the spinning circle. any ideas? Thanks.