Two pressure assisted toilets not working right
We have two pressure assisted toilets in a house that is around 5 years old. This morning I was in the next room to one of our bathrooms and a hear a gurgling noise. I go in and check the toilet and the water level is down. I try to flush it and the it doesn't flush quite right. It takes about two flushes to get a couple of pieces of toilet paper down. It fills up then bubbles or gurgles (I can really tell which it is) at the very end of the flush cycle and then the water level in the bowl drops again. I went to check our second toilet and it's bowl is not filling all the way and you have to flush twice to get the bowl completely empty. I never hear gurgling from the second toilet at the end of its flush cycle but it never even fills up all the way. The second toilet is in our master bath so you wouldn't be able to hear it gurgle unless you where in there with it at the time of gurgling. I went outside and looked from the street and it seems that we only have one outside air vent coming from our house. We are on city water and sewer. The toilets where fine this morning when I woke up. I started a load of laundry and a load in the dishwasher I noticed the toilets after I started those. However they ran through both of there cycles with out any noticeable problems. We went into our crawl space and didn't notice any water leaking from any place. Can you please help us? We are at a loss. We are a young couple who live away from their family and even after talking to parents on the phone parents are at a loss.