Slow GPS fix after updated to firmware 14.20 APAC

My Mk2i takes forever to get a fix on GPS after it was updated to firmware 14.20 APAC.

On firmware 8.60, it took a minute or 2 at most to get a fix. Now it takes about 30 mins. Sometimes it never shows a green bar even it has located my location on the display and a full red bar was shown.

I have tried GPS only, GPS + GLONASS, GPS + Beidou and UltraTrac. None improves the performance.

Does anyone have a similar issue?