From the day I bought my phone new shortly after it was first released, the GPS was all but non-functioning. I.e., I'd get a fix once in a blue moon.
I bought a replacement flash cover but it made no noticeable difference.
I was ready to do a mod but had to send my phone back to HTC for other reasons. I also requested they fix the GPS due to its crapness. I've written more about their UK warranty procedure here: http://forum.xda-developers.com/show...8#post25984478
Unfortunately the GPS, although technically better, still wouldn't achieve a lock hardly any of the time.
So I tried a little solder on the flash cover contacts. But as this was my first time soldering outside uni many years ago, I burnt a contact off entirely!
I bought another flash cover to try again and soldered more carefully. Still no joy, except while I firmly pressed on the lens cover.
So I thought I'd try again. This time, before soldering, while trying to pull the contacts fixed to the phone up a little, one broke off
So getting desperate, I soldered a little more on the flash cover contacts. I also ensured the solder was higher on the contact that would connect to the one broken on the phone.
SUCCESS! Now I get a full 8-12 satellites nearly immediately. Clearly the DHD GPS design is utter **** but at least we've solved it together.
Edit: Grrr [insert swearword here!] It stopped working. It could find satellites okay but without enough strength to determine my location. I'm going to get another flash cover and try again...