All of a sudden, QGIS 2.14.4 hangs on startup on Win7 for at least 2 min. Eventually it starts without error. Hardware is not the issue (Core i7, 8GB ram, etc.). I tried reinstalling with OS4Geo installer and with standalone installer, but no change. I even cleared registry entries and .qgis2 folder. This error began after trying to connect/use a bluetooth GPS with the GPS Tools plugin. QGIS also freezes for a minute when clicking the GPS Tools button, so I suspect that this performance issue relates to the plugin in some way.
Any idea how to improve startup time?
UPDATE: Having uninstalled/reinstalled multiple times, deleted .qgis2 folder, and cleared registry, QGIS 2.14.4 still takes several minutes to start. I may try 2.16.1. Any insight into the processes running during the "Setting up the GUI" stage might be helpful.
UPDATE 2: Version 2.16 has been installed with the same result. For some reason, when my computer is connected to the network via an ethernet connection, QGIS takes 4-5min (as detailed above). However, when connected to my network via wifi, QGIS opens in about 20 seconds.