Problems in making calls to the pstn

Hello, I installed two A1200P on a PC, and I have submitted the following issues:

1) when I make calls to the PSTN from any extention, mark the number and press the send key on the phone, and makes an asterisk delay of 5 to 8 seconds before the call for some channel zap.

where or how I fix this problem so that when you press send, do not make this delay.?

2) The second problem has me paranoid, because not to do to correct it, every time you make a call to the pstn, Many times the operator of the pstn gives me a message the number you've typed is invalid, or if I dial another number from another place, not that I want.

Please can you help me.

PS: excuse my English, I'm not very good.

1) I don't think you can fix this delay, you should understand asterisk is a software IPPBX, every step what dialplan do will waste time.
it's a normal that use 5-8 seconds to call out, can you show the dialplan when you call out?

2) Please replug the fxs modules to check if this problem is gone.