You shouldn't need to change the hardware settings unless you are using an external GPS receiver. But by all accounts it appears the hardware settings are hard coded into GPS enabled ROMs, so you can't change them if you wanted. See this thread for more info:
http://forum.ppcgeeks.com/showthread...gps+hard+coded
FYI, sometimes the GPS will just stop working, especially if your device runs low on memory. As you discovered, a soft reset will fix the issue.