Low FPS when walking / running, High (Normal) FPS when sprinting / combat

[sincerity2103]

So, started a new save, occurred a very weird FPS issue; low FPS when walking / running, around 10-15 FPS outside, 30-40 FPS inside; high (normal) FPS when sprinting / combat, around 60-70 FPS outside, 90-100 inside.

 

Anyone encountered the same problems?