I bought The dishwasher over year ago and everything was fine till now. The dishwasher started to meak grinding noise on the beginning of the cycle. After less than a minute starts bip and smart light flashes. I do not touch it and leave it for about 5 minutes during that time dishwasher flashes few time and start to wash as usual. The dishes are perfectly clean. I've done that about 4 times and it makes that noise every time. I checked hoses, filters are clean. What can cause that noise?