Cracked turbo support arm

At 640 hours on my 914 in a Sling 4 airframe I noticed this crack in the turbo support arm..

l have had a vibration issue for the last 30 hours or so.  I am not sure if this crack was caused by the vibration, or is the source of vibration.

l have recently had the carbs overhauled. Gearbox removed and inspected. A propeller balance performed .

Had anyone come across this?

cheers

Simon