How to control my girlfriends anger problems?

I have been with this girl for almost 2 years and I love her very much but the only problem is she has a very short temper. And when I say very short I mean extremely short. She admits she has it also and wants to get rid of it but does not know how. An example of her temper is. If I am sitting in the other room and she calls me and I do not hear her she will yell my name again and I will come over and she will say to me. Never mind I don't need your help anymore go away!! That doesn't sound bad but the way she says it is very y. Another example. We will be on the phone and for some reason wind is blowing and she can hear it on the other end. She will get extremely annoyed and have an attitude with me for a few minutes. Like she will ask what the sound is and ill say I don't here a sound. She will say whatever and just be in a mood. Then I get annoyed because she started getting y with me and I yell at her and that makes it worse. Now I love this girl very much. I am planning on asking her to marry me. But is could this attitude just be her personality or could it be a treatable disorder? Now minus this attitude everything else about her is great. This is not 100% of the time it probably happens once a day for about 10-15 minutes then she calms down. But it just seems she gets annoyed and ticked off about things that me or other people would not get annoyed about. She usually doesn't stay angry for a long time either. At most is lasts 30 minutes but she is usually over it in 10-15 minutes. Now once again she even admits she has this problem. So is there a cure?