How is your technique taking your meds?
I don't mean to sound like you aren't taking your meds right, but sometimes something small can make it so you don't get the medicine you should. Your advair, do you always keep it horizontal before you inhale? Do you use a spacer with the rescue drug? Do you hold your breath after even if only a couple of seconds? Do you take your rescue first? Do you inhale with the inhaler slowly, do you inhale with the advair fast?
You have probably been over this, but if not, you might want to ask your doctor just watch you take your meds to see if there is anything that could be done differently to improve the dossages you are getting. Again, Its just a thought......
Also, if you experience attacks often you could see about getting an nebulizer for albuterol during your attacks. Some people find it is more effective, (studies debate this) but in the hospital many times during severe attacks we give a continuous neb as we find it to be the most effective. Of course you wouldn't want to do a continuous one at home, but your doctor could tell you the limit before having to go the ER if symptoms do not get better.
And besides the steroid included in the advair do you use an anticholinergic? Atrovent has some drying and brochodilating effects and can help as a maintaince drug. If you decide to stick with the nebulizer route Duoneb is an alternative where it combines the rescue albuterol and atrovent together.
I know you have probably already been told to try to avoid triggers ect. So, it's just some thoughts of some things that could help you.
Talk to your doctor about control and maintaince.