System.InvalidOperationException: Failed to compare two elements in the array.

Hi,

Over the past couple of days I've received random crashes while playing. I can't note anything in particular I was doing at the time of each crash, but it seems to be happening more and more. The vast majority of the time the crash has been immediately to desktop, but I got the option to report to Klei twice. As far as I can tell it's always the same error:

System.InvalidOperationException: Failed to compare two elements in the array. ---> System.NullReferenceException: Object reference not set to an instance of an object
  at System.Collections.Generic.ArraySortHelper`1[T].Sort (T[] keys, System.Int32 index, System.Int32 length, System.Collections.Generic.IComparer`1[T] comparer) [0x0000b] in <8ce0bd04a7a04b4b9395538239d3fdd8>:0 

As far as troubleshooting is concerned I've used Steam to validate my install and I've rebooted a couple of times. I don't run any mods or anything.

Thanks for your help in advance,