Do you mean firmware?
You can download the old firmware from Bitmain website from here https://service.bitmain.com/support/download?product=Antminer%20S9
Are you still having an issue with one hashboard?
Can you post the whole Kernel logs here so that we can analyze your miner's issue.
You can find the kernel logs under system>kernel log> then copy them all and paste it to pastebin.com and put the link here or paste it here as a code.
Don't forget to put the Hashboard chain(7) then run for 15 minutes then start copying the kernel logs and post it here so that we can check if the chain (7) has PIC fw issue.