I have a brand new vacuum (dyson) that trips my breaker. Never happened before this except once when I ran 2 other vacuums at the same time
There are several common problems with high performance vacuums and circuit breakers. First a vacuum may be drawing close to the maximum amperage on a circuit but with most circuits there may be a few other items that push the total current being used over the trip limit (very common on 15 amp circuits and even happens on 20 amp circuits). The second cause that I have seen in the last few years is AFCI or arc fault breakers, they can not tell in many cases the difference between a dangerous arc that could start a fire and a motor's brushes arcing so they trip. The last case is GFCI breakers, I usually see these trip on start or stop with motor loads because of how they start using capacitors to create a phase shift that can create a small amount of leakage in the ground path causing a trip. Of course it could be a real fault in your new vacuum but in my experiance this is rare but should not be ignored. Try a different outlet that is on a different circuit breaker, if it works there great if not see the 3 possible problems above or call Dyson since 2 circuits having trouble may point to a problem with the vacuum.
Could simply be the breaker has become weak and needs replacing. Any type of breaker can become weak, but chances are its a standars style breaker, with one wire. It happens, I've replaced them before because of it. Look on your vacuum, it should state somewhere on it the it's power requirements. If it doesn't plainly state it's amps but states the volts (normally 110 or 120) and watts use this equation to figure it out. Amps=watts/volts. If it is lower than the breakers rating(likely 15amp), which id never seen and don't think i ever will see a household vac requiring more than 15 amps, and nothing else is powered on in that circuit than your breaker likely is just getting weak and will only get weaker. I change my own breakers on do it for friends and family, along with other electrical work. But it requires the removal of the cover. I do it with the main on but i recommend others who will try it theirselves to get someone to hold the light for them and shut off the mail breaker. Even with the main off the cables coming into it as well as the lugs will be hot/live and touching them can hurt if not kill you. You shouldnt be anywhere near them to change a breaker. You can findout your brand and watxh a YouTube video for removal but all the ones ive done you shutoff the breaker. The sides towards the center of the pops pops out first(i push the reset lever towards the off position with a firm jerk) itll then swing on the side with the wire. Grab the breaker by the sides(dont hit the reset lever) and pull it out towards you, if you swing it on the pivoting sideto far it will become harder to pull it out since the clips face on a 90 degree angle from the face of the breaker. Give it a quick short jerk. Since the wire is still attached. You may have a foot of wire to play with or 3"so dont go crazy yanking it out. At the point the breaker and connecting wire is dead. Then loosen the screw holding in the wire. Screw will likely accept a large flat head but some accept both a flat and a square drive which has less of a chance of slipping. When the wire is removed hold it to keep the wire from springing back in towards the hot rail. Then simply push it into the new breaker, tighten screw, pop outside of breaker onto rail, then inside,(some say to shut off breakers off, guess it doesnt hurt) main power on, breaker(s) on.