A mobile electronic device and method is disclosed. The mobile electronic device includes a detection module, a first memory a second memory and a clock control module. The detection module is configured to detect a user input to make an emergency call. The first memory stores one or more first clock rates. The clock control module configured to perform select one of the one or more first clock rates as a selected first clock rate such that an odd-multiple of the one of the first clock rates is different from a carrier frequency of a positioning signal that is received from a global positioning system. The control module is further configured to perform set a clock rate of the second memory to the selected rate in response to a detection of the user input.