Hello Anthony, I appreciate your response, it is encouraging. While I was waiting for a response, I took a stab at cleaning up csound4-gbs for big endian and lp64 systems. I found some ambiguous usages of int, but it didn't take me long to run into the hairy memory/pointer/bit manipulation in the Csound code, (ie: incorrect memory allignment and size allocated for data structures). I was under the mistaken impression that csound4 was already 64bit clean and that my problems were only the result of some bitrot. It is a larger task than I am prepared to take on at this time. I'll just use csound4 on a 32-bit system and start looking at csound5. Thanks again for the guidance, Ben