Weather depiction problems.

Sometimes I have severe troubles with ASA:

1) TAT goes up sometimes to +30°C in flight even on hight altitudes.

2) Sometimes when the METAR reports e.g. 13003KT 100V160 3600 BR SCT012 SCT017 BKN048 03/00 Q1020 the temperature remains at ISA temp (+15°c) on the ground and QNH 1013

3) Sometimes nothing changes in the FSX weather engine at all, even it says in FSX 'Initial weather depiction complete'

ASA runs on a networked computer, however i have tested SimConnect but i can't find any problems with my connection. It is all very strange... because it happens not always