My game started off ok and Skyrim runs fine on my pc. Have quite a lot of mods running.

I could drop stuff out of my inventory on the ground and see it roll around or place it somewhere throughout the first part of the game (around riverwood). After I did the "Golden Claw" quest however, I noticed that whenever I dropped stuff it would disappear as soon as my inventory would close, or even stranger I would see it just drop straight through the floor.

This now happens in interiors or in the wild.

The only mods I installed before this started happening was "FNIS Improved Animations", "Duel Wield Animations" and "Duel Wield Parrying" mod. Maybe they were just the straw that broke the camels back?

Has anyone else experienced this problem? Could performance issues be causing the game to remove "extra" items that I place in the game world? Please could anybody give advice about this? Thank you.

Strangely, any arrows I shoot from a bow stay in the world and don't disappear unlike objects I drop.