I have just got a pair of Shure SE210 headphones and I know this is a stupid question and I didn't know where to put it but how do you take the headphone plugs off? I have the squiggy ones it came with on and want to try out the alternative ones. But I have tugged quite hard on them and they don't seem to want to come off. I assume that you just pull them off? Do I have to twist them?