When I get going in the morning, on the first or second shift with my standard transmission Mazda 3, I hear a noticeable "ping" from somewhere in the front end. It doesn't happen again.
Ping from front end on first or second shift of the day on 2008 Mazda Mazda3
I'd suspect that there's a CV joint starting to bind up. Just a guess. Check for torn boots on the driveshafts, if the boots are torn then the lube is gone and that could be your trouble. Next thought is that there's a loose bolt in a motor mount or a failing motor mount. Third thought is that there's a loose bolt in the engine cradle where it bolts to the body. Make sure your wheels are torqued right and that the axle nuts in the hubs are torqued right, or at least not loose. Any front end work lately? If so, check the work for something loose.