OpenRocket Behaving Weird
 

I've used OpenRocket quite frequently and never run into a problem like this. When I simulate a flight, I'm getting about double the expected altitude and a huge decent rate (~200 ft/s) for all my designs. Even using the sample rocket provided, this is happening. Even if I use the same configuration and just re-run an old simulation, I get weird results. The original simulations don't match the new ones. I think I must have changed a setting somewhere but I can't seem to find it. Any help would be greatly appreciated.
Thanks!

Chris,

Go take a look at launch conditions (specifically barometric pressure). Sounds like you've gotten way far away from the standard atmosphere somehow.