The VD cords do pose quite a bit of a problem. Firstly, they need to be pre-bent into shape so that the female end can roughly fit into the socket of the equipment. To secure the female connector, I use CD cases and folded paper sheets to support the connector. I know it's little unprofessional but that is the only way I can think of to prevent the connector from sliding off the socket. I have tried blu-tack at first but without any form of supports beneath it's virtually impossible to secure the connector to the socket of the equipment, not to mention the cord was actually pulling the whole preamp off the rack without the support!