Doesn't mean it isn't a dry joint tho. In one case of a TV I found one, and it worked, but then another reappeared. I fixed that, then another..in the end I sat there with a lamp and resoldered every singly suspect looking joint.
The TV was faultless until the Great Lightning Strike that took out half the house wiring fried it beyond economic repair. It was a second hand ex rental and had done me ten years by then so I didn't reckon it owed me anything.