Yes this might happen if you have RMM2 installed, and you used drive redirection. The board will try to boot from the virtual CD/DVD. Also with BIOS 98 it will not skip CD/DVD drive when there is no bootable media, if RMM2 is installed.
Please try BIOS 99 which is supposed to fix the boot order issue. Another workaround is to set your RAID controller as first boot device. Also disable the RMM2 virtual CD/DVD as a boot device in BIOS.