Weird noise. i have a eureka the boss and i am getting a weird noise figured bag was full needed

Question

i have a eureka the boss and i am getting a weird noise figured bag was full needed to change it so i did. Noise persisted so i checked make sure nothing was caught in the brushes. I even checked the belt it was fine replaced with a new one.Still the noise is there help me I am out of what else to check.