The heater is trying to warm up the water through a layer of sediment that has built up on the inside of the heater.
The bathroom farthest away from the water heater might take a bit longer because of the distance the water has to travel.
In water piping systems, usually at the end of a pipe run, an air chamber is installed to relieve water hammer. Sometimes a dishwasher with...
There could be an obstruction in the floor drain line. It could also be caused by the main sewer line.