Thanks for the reply. I took a look at Sean's site and it seems that choosing the right firmware for your DVR can be tricky so he e-mails firmware to customers by request and since I didn't buy mine from him then I can understand he may not want to go through the trouble. I also has a look at Bahamas Security and although they seem to have a TON of great info and tools, firmware do not appear to be among them.
Maybe one of them will be kind enough to reply with a suggestion. I would have expected Dahua to provide unbranded firmware for their devices but perhaps they had too many issues with people using incorrect firmware for their DVR.
Thanks!