Tray not closing using DVD-r's

[there is light]

I have just bought a Pioneer 105, and tried to back up some of my games.
I have a 30003 version 4,
AR2/v2, neo 2.2, GTA3 orig, Infinity DVD-r, Recordnow max, Primo DVD and the latest Nero, Tried Memorex and unbranded DVD-r.
If I follow the boot methods discribed on this forum by BG and everybody else, all is well until I release the reset switch, the tray comes out to replace with the back-up as you expect, but then it won't go back in on its own. You have to press eject for it to return, if you try to push it to go in there is a dead feel and it won't motorise itself back in (usually it does), and then the game fails to load.

Any Ideas, it driving me crazy, ive spent hours trying all different boot methods.