Strange EMC2 Bug

Has anyone experienced a bug where the program will be running, and suddenly it will jump back to a previous point in the program? It does this repeatedly.

I have experienced this many times under the following circumstances:

1) Running a large program (I checked RAM usage however, and I am well below capacity)
2) Using subroutines. (However, it jumps from outside of a subroutine to the very middle of a subroutine, and not always to the same spot)

I have checked and double and triple checked the code. This is, needless to say, causing very bad things to happen (crashes, etc), and rendering my code/machine useless. I am using EMC 2.3.5. Seems like a bad pointer or something.

Thanks!
Nic

2) Using subroutines. (However, it jumps from outside of a subroutine to the very middle of a subroutine, and not always to the same spot)

UPDATE: I replaced each subroutine call (e.g., "O100 call") with the contents of the subroutine, thereby eliminating the subroutines altogether. This fixed the problem. There is definitely a bug in EMC2 related to subroutines!

NOTE: I was a bad scientist, and I manipulated two variables. The other thing I changed is that I removed the line numbers. It seems very unlikely that this would do anything, but ya never know.