Fast forward & rewind problems with TNT

When I watch basketball games recorded to DVR from 737, I can fast forward or rewind or go 30 seconds back smoothly.

When I watch basketball games  recorded to DVR from TNT, it is impossible to skip commercials.  Is there collusion between Xfinity and TNT?  I wonder.    I hit 30 second back button and it jumps forward 3 minutes instead.  If I fast forward through commercials it proceeds (even with five arrows) at the normal pace through commercials but then jumps forward 10 minutes when it hits the game.  There is some kind of deal.  There must be.  I will not watch TNT again - even recorded.  This is wrong.  I pay for a service   Thanks for nothing.