Game runs in super-slowmotion, but only in Galaxy S2. Not low framerate, slow motion

We have this really strange problem, on the Samsung Galaxy S2 our game is running as if the timescale is set up like 0.01 or something - it takes half an hour to do something that takes 5 seconds on all other devices. We first thought it was a hang, it was so slow, but we have a title screen logo that starts tiny and scales in, and we noticed that if you wait long enough, it does actually get bigger. We have like 8 different Android devices in the company, and a bunch of iOS devices, but it’s only the S2 that has this strange problem.

Any idea what could cause this? The game used to work fine on it.

This was caused by Multithreaded Rendering, I disabled that and the problem went away.