Help to diagnose possible bearing noise.

[lewis328]

E90. 330d has been running fine, until today when pulling away at slow speed, I can hear a light metallic rattle. I checked under car (not on ramp) I can see nothing obvious, nothing hanging loose, or broken, I am wondering if it is the start of a bearing failure, I can't tell if it's from the front or rear, rather annoying. Anyone had similar, or can shed any light on issue? Steering etc not affected.

Thanks in advance.