I've been having this issue with Odin lately and I'm really at a loss as to how to fix it, and I find myself becoming a bit frustrated/discouraged.
He has become very.. "meh" while doing obedience. Heeling can be sluggish, lack of focus on handler. Recalls are at a snail's pace. If I place him in a "fuss" he will sit on my left and give me attention until we start moving.
I have tried reintroducing treats, tugs, balls, etc. with minimal success. I have tried upping my energy, moving faster, acting excited, all that good stuff and I'm not really getting anywhere either.
Outside of training he will play/tug enthusiastically, I can get him all fired up. As soon as he realizes we're going to work obedience he checks out. I try to make it fun by using the items I know he loves, but there has been this strange disconnect.
I don't even push him to work very long/often anymore either. We may do 45 minutes once a week, and then I'll try and do short 5-10 minute sessions throughout the week. I just now grabbed his tug and tried to do a short session of recalls and I was able to get one decent recall before he started losing interest and I put him up before making anything worse.
I don't really know where to take things from here. While he is correct 90% in the time in the work, he just looks bored out of his mind.