Calling - Hangs up

Hi Guys,

I am having some trouble, almost every call i have the it hangs up in the middle of the call.
I think it happens more when i call to someone, then when receiving.
What this could be?

best regards,
Pedro

ASUS boot screen loop and hangs

I have tried flashing my ASUS transformer TF101 with a SD card and with easy flash software and still no luck at all.
If anyone could advise me on how to flash the TF101 properly that would be really appreciated. Maybe I didn't flash it right or maybe am doing it wrong.
The table boots up and hangs at the ASUS logo screen and a dotted circle go round and round and never continues on to boot up.