In a multi SIM (subscriber identity module) mobile wireless product featuring multiple modems to achieve simultaneous active connections (MSMA—Multi SIM, Multi Active), each SIM card can be either statically allocated to one modem, or dynamically allocated between modems.  In the latter case, a multiplexer switches the SIM data-paths between the various SIM cards and modems.  Thus, there may be a need for an efficient and effective switching between the various SIM cards and modems.