Help! Soft shelled eggs

[SwartPeper]

Hi Everyone! I have an EE, Noodle, that started to lay about two to three months ago and out of that only 4 of her eggs where hard shells and laid in the nest-box. Two large and two small. Now each morning there is a soft shelled egg on the dropping tray, so it happens in her sleep or early morning (please see photo of the one large egg she laid and the very pale soft shelled egg I get each morning - this is still a good example, most of times it is broken and all mushy). They get normal mixed feed, layer pellets and always have access to oyster shell (I have not seen her eating it really). They get lots of veggie treats (like fresh corn, broccoli, carrots, cauliflower, etc) and some cheese or plain yogurt occasionally. I also occasionally give them a multi-vitamin in their drinking water. She really does not look sick at all, even comes into the kitchen to ask for some treats. Just don't know how to fix it, any advise perhaps?

 

[Pork Pie]

I'd try cutting out all additional treats and leaving them to eat only the layers feed.
This is a helpful link -
http://www.backyardchickens.com/a/common-egg-quality-problems

 

[ChattyChickens4Life]

This may be caused from a lack of calcium. The egg shells need calcium to be hard. I would suggest getting crushed oyster shells from the poultry feed store, or crushing up the hard egg shells. Just mix this in with the feed or put it in a small bowl. Hope this helps!