You need to find the exact location of the clog. It sounds like something solid like a nail through a pipe. If all ports are bad then it is between the closest port and the unit. Did you try a small plumbers tape from the unit into the hose (not from a port towards the unit)? Get the suction working as good as you can, put a paper towel through the first port while putting your ear on the wall. However may thuds you hear is now many turns the clog is away from the valve. We are trying to find the location so can you see if you an access the pipe to cut it and clear it or repair it. Also, when things are quiet in your home, turn on the unit, put the hose in the furthest valve, then go back toward the first inlet and unit and put your ear on the wall. You should hear the clog rattling. Find it, access it, and repair it.