Jane(posted 7393 days ago)DLA - being solicitors you could consider complaning to the Law Society and the Office of Fair Trading. I think the office of fair trading have recently brought new rules in to force re the companies involved in the collection of debt. If your parents are BT customers they could contact BT and ask about their "choose to refuse" which is free for the first month. Basically it will allow them to bar DLA from phoning them by keying in a code on their phone the next time they phone.
Have you actually acknowledged the debt??? If not you might want to consider making an ex gratia payment on the basis that you are not admitting liability. Now that you are not working and I'm assuming you do not have any other assets you might be lucky enough to have an offer accepted. ( e mail me and I can tell you what they accepted from me - similiar circumstances )
I hope this helps in some small way.
Moira