The issues earlier this year had to do with a caching file that the watch holds to make satellite lock quicker. That file was corrupted so the lock was off. That hasn't happened in a while and when it does it is reported on because it impacts a lot of people. It is possible there is a problem with your watch's file which I believe can be refreshed with a hard boot and then going to get a new satellite lock.
Sometimes there are also some issues if you are are near buildings. I had this activity below when I was in Chicago for one day this summer. It took forever, close to 20 minutes, for my 945 to even get a signal and I was out near the shore. Obviously something was off because there was no swim involved in my run and I've yet to master walking on water. Sometimes the angle of the satellite is very low in the sky and even short building can cause issues. Now that I have the Epix 2 I'm hoping the additional satellite options help.
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The actual run began and ended at Grant park, went down the south bank of the river and back up the north bank, and included a little bit of the Navy pier.