Airport base station disappearing

Hi

Last week when I booted up my Macbook Pro it would not connect to my network - I could see my network in the airport menu item, tried to connect, was asked for a password, put password in - time out. Eventually I unplugged the ethernet cable from airport and plugged it into my computer and I was on the internet. I then did a factory re-set of my airport = everything OK. Then this morning I booted up and again couldn't not connect. Unplugged airport, plugged back in = OK. What is going on? Anybody any ideas? Is this an Apple issue?