This sounds EXACTLY like my Chase when he was younger! He had 2 spots in the bedroom, and 1 by the bathroom door where he was chewing the walls! I tried the bitter spray, but that didn't help. It was only when we were busy (eating dinner, showering, making dinner, etc) that he would do it, and he didn't do it in front of us. What helped was giving him a frozen Kong or bully stick while we were eating, not shutting the bathroom door when I was in there, and he stopped completely when we brought Calvin home (he was 13 months old then). His brother kept him busy enough not to get bored, and thankfully Calvin never tried to chew the walls
