Hello community ,

I have had my N900 for a while, but starting yesterday, it started having what appears to be GSM connectivity issues. I search around and found a lot of people have the "no sim card" error. However, mine is different: the phone goes from having strong signal and 3g signal to 0 bars, or sometimes, it goes from a strong signal to the red symbol indicating no SIM is inserted. After a few minutes (non consistent amount), the phone usually restores the connection. Restarting works sometimes, but others it turns on with that symbol/no signal for a few minutes. Also I would like to note a few other weird things:

The phone restarts itself (not frequently, but maybe twice a day), and it takes longer than it used to to power up. Also, sometimes it comes up with the message popup about time, timezone, and such. What I have tried:

1- I restored all kernel settings to default settings ( I had it overclocked to 850- Didn't work)
2- Replaced my SIM with a brand new one. ( I have T-mobile).
3- Made SURE my SIM is inserted PERFECTLY!

Some people have suggested putting some sort of paper between the door and the SIM, others suggested to re-flash. However, I dont believe either of those options will help me since my case is different (it only does it sometimes). I would really appreciate it if somebody has an idea of whats going on, or what I could try. Any help is very well appreciated. Thanks again!