Yeah I tend to agree with you that it is a hardware related issue.
This is going to sound off the wall but please do try it. Could you physically remove the Blu-Ray player (remove the sata) and see if your problem is resolved.
I had this exact same thing with a Pioneer Blu-Ray installed. No idea why to be honest but once it was removed the problem was gone.
Or if you wish, this is the more comprehensive option. Please remove your motherboard from the case and use the box it came in as the test bench.
With only the bare minimum of hardware does your board make the sounds?
To help us help you - please provide as much information about your system and the problem as possible.