My Eureka Boss vacuum belt keeps breaking

I have been searching the machine for something which could be rubbing against the belt to cause it to fray and break as often as it does. So far, I haven't found anything. I have heard that the belts, called ribbon belts, are terrible! I find that the belts break faster when I use the hose. I haven't found a way to make a belt last longer.

i noticed that the belt actually drifts off center causing the edge of it to frey

How long hace you had your vacuum? THe belts on this vacuum are actually supposed to last a really long time. If the belts brake faster when your using the hose that impies your clutch which tightens and loosens your belt to keep the brush from spinning while the vacuum is upright couild be malfuntioning. If you post your serial number i can tell you if your still under manufacturers warranty.