Is the filter level? Is the media 'basket' assembly firmly in place? Sometimes if the 'basket' doesn't 'hook' properly to the piece that fits over the impeller it can rise up and cause overflow.
BTW& FWIW--vaseline (petroleum jelly) is an improper lube for o-ring material--It has a detrimental effect on most materials commonly used for o-rings. Use silicone based or if that's unavailable, vegetable oils in your kitchen are a better choice. Not applying anything is better than using vaseline.....
"Since petroleum jelly is oil-based, it interferes with the structure of latex. Using petroleum jelly with latex condoms weakens the material increasing the chance of rupture"--Wikipedia
BTW& FWIW--vaseline (petroleum jelly) is an improper lube for o-ring material--It has a detrimental effect on most materials commonly used for o-rings. Use silicone based or if that's unavailable, vegetable oils in your kitchen are a better choice. Not applying anything is better than using vaseline.....
"Since petroleum jelly is oil-based, it interferes with the structure of latex. Using petroleum jelly with latex condoms weakens the material increasing the chance of rupture"--Wikipedia