Sony's troubled mobile division took another hit this year, but in a very discreet way. A new report says that the company's U.S. mobile division moved its offices from Atlanta to the San Francisco area and that change also caused an unknown number of layoffs.

According to Re/code, Kunihiko Shiomi, the previous head of U.S. mobile development at Sony, was quietly promoted to president of the division in January:

The former U.S. head, Ravi Nookola, has returned to Canada and is now CEO of Burnaby, B.C.-based Glentel, which runs a range of wireless service businesses. Nookola worked at Sony Canada before being named to run U.S. operations in January 2013.

Sony launched its Xperia Z5 and Z5 Compact smartphones in the U.S. earlier this year, both as unlocked devices.

Z5 at Amazon Z5 Compact at Amazon