Have a look at some of these troubleshooting tips and tricks.
- How to Troubleshoot "Record Simulation"
- Problem with recording simulation - #4 by marcus
- Popping and errors when recording - #2 by marcus
They almost all boil down to using Extract Simulation to narrow down exactly where differences start to arise.
Let me know if neither of these solve the issue, and what else if happening in your specific case!