Hi k1w1_123,

At first I was pretty sure it is not problem with iGO.
iGO is much better then many other navigation software while it is predicting your real position based on last measured position and speed.
So when moving You can see dot where it got last info and your vehicle moving ahead, with another words - simulating real position, and is quite good in that even when GPS signal is lost (tunnels).

I have friend pretty good in phone electronics, and what a bad luck, he had same problem like You with his phone.
After some experiments and searching www, he found that GPS antenna in his phone is bad, not broken but bad construction.
Hi tried many modification with small improvements, but it was never good as it should be.

If there is problem with GPS module or with antenna (and probably is), I'm afraid there in not much You can do.
Take it to nearest repair center to see if they could help.

Good luck.