What would cause a gurgling sound at the kitchen sink when no water is running anywhere in the house?

House is two story with kitchen with two basin sink and a bathroom with toilet and sink. The kitchen trap services both kitchen sinks. House is on a fairly steep hill with a number of houses on both sides uphill. A street behind the house has houses at a lower level. There may be more than one problem. Not only is there gurgling only heard at the kitchen sink and not from the second basin which has a disposal, I noted a number of other symptons. I could hear the sound of a considerable amount of water running coming from the drain while the gurgling was taking place. The sound would last for only a few minutes normally, but many times during the day without water running in the house. Thought it might be improper sewer hookup where venturi effect from the sewer line running down the hill would pull water from the trap if the vent for the sink is also plugged up and that would allow the sound of the water rushing by to escape from the sink drain. To test that, I put the stopper/strainer in the sink and put a small amount of water in the sink to prevent any air from moving into the drain and to prevent the water from being pulled from the sink trap. That stopped the sound. I kept this setup going for several hours. I am not sure, but I thought I heard the gurgling later for a short time, but the water in the sink seemed undisturbed. The surprise came when a few hours later, I pulled the stopper out of the sink. A gallon or two of water quickly boiled up into the sink and then drained slowly out. The water was not clean, but also not gross. Normal water from the sink never seemed to drain slowly. That is what makes me think there are two problems. If the street sewer line draining was providing suction on the house sewer line, the vent should provide the air if not plugged up instead of the sink. However, I cannot explain why plugging the sink drain caused a build up of sewer water in the house, apparently filling the house sewer or vent lines to a point higher than the sink drain. It is possible that during the time the sink drain was plugged that water was run in the house because I did not think to note that as possibly significant. Explanation and solution?