You should not have to force an Almanac Update by using the Factory Reset that often. If you have a good gps signal, it will pull in updates automatically. The issue is if you are indoors with a poor signal and it tries to download a new almanac. It could potentially not download a complete almanac and that could affect your signal acquisition. That is until if gets a complete, good almanac.
If it is only losing a signal every once in a while, that is likely interference or solar activity. If it is prolonged and frequent, then you might have bad or incomplete almanac. Hope this helps.