Samsung Galaxy S2 phones with the SiRF StarIV.
if your GPS has issue , try the following:-
1. Clear AGPS data . Use the app GPS Test (go to settings and select Clear AGPS)
2. Turn off GPS on your phone, switch the phone to airplane mode, Turn GPS on.
3. Use an app like GPS Test to monitor the satellite signals until you get a position fix. This should take a few minutes.
4. Now you can turn airplane mode off and do business as usual.
When the problem reappears, repeat step 1 to 4.