Problem Rebooting F2812 from external Flash

I am using the F2812 DSP on a board of our own design that is in production, using CCS 3.1 and DSP-BIOS 4.90. My application runs fine from internal FLASH or external SRAM. I am trying to create a version that can switch from Internal FLASH to SRAM dynamically by copying a new .OUT image from external FLASH to external SRAM then doing a long branch LB asm command to the new _c_int00 startup function. The image is known to be good and is built with the external SRAM map. The problem is, it is not reliable when jumping from the internal FLASH image to the external FLASH image (after copying it to SRAM). The program will lockup or runaway sometimes, but other times runs fine. When it locks up, it appears to start to run but dies soon after main() starts. I would like to know if there are any warnings or gotchas to note when trying to restart a new code image on the fly using DSP-BIOS. i.e. if I disable interrupts and do a long branch from internal flash to a new _c_int00 vector of a different application in external sram should that work without further CPU initialization?