As per the project shared by the OP (see question comments), it seems the tab bar image insets seem to be messing things up.
Steps to resolve the issue:
- Select the tab bar item of the problematic
ViewController
s in IB - Go to Size Inspector section (on the right)
- Ensure your image insets are balanced
- If you give 5px inset to top then balance with a -5px inset to bottom
- If you give 5px inset to left then balance with a -5px inset to right
I have no explanation for this, sorry... but if anyone does then kindly comment/post