Sorry for late reply...
OK, here are the details for my problem.
I use a no-solder-mod v5 from lik sang and a AR2 V2. My PS2 is a 30004 R.
I had no problems to play backup games till i´ve inserted a cd-r wrong. It was not placed right and when tray closed cd-r was inserted not fully. It had to be take out manually. So I pulled out cd-r and since then the swap does not work. When I try to swap after AR 2 has boot eject light is blinking as usually when you swap and it makes also the same swap noise but the tray won´t open.
When you press eject button normal dvd try opens but when you hold it down for swap it doesn´t.
I think that my mod chip is ok.
Could it be that the problem is in my dvd tray, e.g. sth. is broken when i manually took out cd-r?
Thanks for your help