We recently changed internet provider and since, it's been a bit dodgy on my Macbook Pro. It connects to the internet fine (as it is now) but occasionally (3 or 4 times a day) it'll die. The laptop says it's still connected to the network, but I can't access any websites or use the iTunes store, etc. I'd have assumed the network itself was down if I weren't able to access it on my phone. Usually the blackouts last about 20 to 60 minutes. Any suggestions? Thanks.