[drh4683]

the 14DC15 is a 16" portable color hybrid set. Has something like 14 tubes or so. I have a few of these and have never had this type of issue, so I dont have a specific answer. Since you mention it gets better as it warms up, that means its a thermal problem within one of the components. Get some electronic freeze spray. give each cap in the horizontal frequency section a shot while its powered up. Problem will be revealed once the set reacts to the cap that was sprayed. It works very well for finding the troublemaker. good luck.