Strange characters appear when distribution link is clicked

Description of issue or problem I’m having:
Screen shot attached for ready reference. strange characters appear on screen when distribution or other links are clicked. I appears for a brief period and then disappear before normal screen is shown.

Steps I took leading up to the issue:
check the error logs but found no clue.

What I tried to resolve the issue:

i enabled gettext php extension.
Application Version - e.g., OJS 3.1.2:
ojs 3.3.8

Additional information, such as screenshots and error log messages if applicable:
screen shots attached

The language file terms you see on the screen.
In my experience, you usually encounter it when the server/site is running slow.

Yes, You are right but it behaves normally with other journals running 3.2 versions…
What solution you suggest please as journal users complain about this issue…