A tank refill tube that is too short may be causing the toilet noises. Slide the tubing about two inches over the end of the refill tube. The free end of the hose that you've added will deposit water silently on the bottom of the tank. A simple solution is to add a tank cover to the outside of the tank. Another method is to install an insulating liner inside the tank.
Kits are available from the plumbing supply stores.
Follow manufacturer's installation instructions. Another way of stopping condensation is to install a mixing valve which adds a little warm water to the cold water entering the tank. This raises the temperature of the tank water. This is not a job for the inexperienced home repair person. Call a plumber for this job.