Engine oil level is fine so that's been checked off.
Took the time and gave all I could inspect a once over. Fluids all look good, took the opportunity to give the MAF sensor a clean as I don't think it's ever been touched. Checked the air filter, could use a change. I believe MMC call for MEP3383 but for the life of me can't figure out where to order it! I've exhausted google searches and searches on TM. Am I missing a trick?!
The above wouldn't have caused the the noise but was good to get things checked over.
Fingers crossed this was a one off fluke