One of our 13yo moggies has developed a "broken" miaow over the last year or so. Instead of a single "Miaaaooow," he now says "Mia-a-ow." Is this anything to be concerned about? He has also increased his miaowing, and gets distracted from eating more easily, sometimes wants to eat in a different room from our other 3 cats (aged 13, 12 and 12 - he and our female 13yo are the parents of the two 12yos, so they are very familiar with each other), though otherwise seems happy, and is active.