12 reg, 50,000 miles, just lately a low noise/rattle has started but only @ 800 revs and goes @ 900 revs. Doesn't matter if rolling, cluch in or out, driving or stationary. It sounds like its coming from around the the glove compartment which I've had out, along with the battery and the little outside grill on the wing level with the battery. A friend has the same problem for over a year and his is 3 years younger.

I've got a video on YouTube about this.
It's often the engine air intake bolt not secured correctly at the factory.
You can check it by removing the grille, to see if the bolt underneath is tight.
 2009 Rimini Red SE TD4. Soon to be sold.
Hyundai Ionic 5 Ultimate on order.
Gone. 2006 Tonga Green i6 HSE.

Thanks for info, tightend bolt 1 turn but made no difference, afraid to tighten any more feels like its going into plastic.

Try moving the plastic back part where it fits to the body. If it's loose like in the video, tighten the bolt until it stops moving freely. If it's not moving, then the issue is elsewhere. The central speaker grille on mine used to rattle on occasion too, but some silicone sealer sorted that issue. 2009 Rimini Red SE TD4. Soon to be sold.
Hyundai Ionic 5 Ultimate on order.
Gone. 2006 Tonga Green i6 HSE.

Alternator (over-run) pulley, has been known to jam up and cause the belt to oscillate.

https://www.freel2.com/forum/topic34499.html?highlight=pulley

https://www.freel2.com/forum/search.php?se...rch_time=0 FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 76k+ miles) (MY2015)