Disc will not load

No there will not be a easy fix for this. You can keep putting up with this the way you have been or buy a new receiver and try to sell this one on craigslist, eBay, etc.

clean the laser lens with one laser disc cleaner

You have a slack loading belt under the tray.The loading action is not being completed because of it.
The Cd lifting mechanism requires more torque than the tray rotating action. If you put your ears close to the tray you will hear a belt slipping sound after the loading tray goes in . If you push the disc motor assembly with your hand from underneath the action sometimes get completed and the cd will start playing. Any way you cannot be doing this all the time, the belt needs changing. Its a set of two belts, one very small for the tray rotation and a thicker/bigger one for loading mechanism.

It is possible that the loading belt needs to be replaced, or the timing gears are out of sink, either way it must be taken apart to find the problem, sometimes I find the gears ware out causing the unit to lock up. When you hit the eject button do you hear a motor running? that should be the sound of the loading mechanism trying to eject the tray.

Try cleaning the glass laser eye lens with rubbing alcohol and a cotton swab. If cleaning doesn't work, you may want to change or laser eyee unit.

I have the same exact problem with my Onkyo C-707CHX and I found a solution that doesn't involve jamming any screws or other metal objects into your cd tray (which could most likely just cause more damage). This way seems a little safer: Power on your device and hit the open button. As soon as you hit the open button quickly push slightly with both hands on both sides of the cd tray that should be opening. You should hear the trays moving around in there and then you have to try to feel for a slight push from the tray. As soon as you feel that slight push, take your hands off of the tray and let it come out. This has been working for me for a while now (and hopefully will continue to work until I take it to get fixed somewhere). The only issue I have run into is that my "Disc 1" open button doesn't work with this method. So I just use this method with disc 2 or 3 and then once it's open I can hit the disc 1 button to get to that tray. So if it doesn't work with one tray, try the other two as well. Hope this helps.

I fixed this on my unit from a tip on AVS Forum

Unit has "Power on" msg, follow these steps:

1) Hit power button for 5 -10 sec unitl unit shuts off
2) Press open / close button unit or remote first (do not hit power button first)
3) On the third try, the disc tray opened

I had James Bond Goldfinger in the player ( not sure if this had anything to do with it), I put another Blu Ray in and it loaded fine and is playing fine, hope this works for you

Dave

AVS link below
http://www.avsforum.com/avs-vb/showthread.php?t=1054927&page=413

Our started doing the same thing about a week after the warranty ran out. It has to do with the alignment of the discs being loaded. here's a work-around that works for us:
Open the tray
Choose which disc you are going to watch and use the Change Disc button to push the selected disc to the back (ie, if you want to view Disc 1, discs 3 and 4 will be visible in the tray).
Look down the center holes of discs 3 and 4... manually move your tray left-or-right to align the holes with the tray.
Push the Direct Play button on the top right of the unit for your disc of choice (Disc 1 using the example above).

hope that helps... I've searched for a while and played around with the unit (with and without the cover on) trying to figure out a way to re-align the tray, but no luck.

--JeD

The loading mechanism is off by a tooth or 2. The tray out position switch is not being triggered properly and the tray will reenter the machine. Did this just start happening? It is possible that the sensor switches are defective too. Worse case scenerio is about $5 in parts plus the local labor rate for repair.
Dan

Not a solution as much as clues. I was given a SL PD588 by a friend 'cuz it stopped working. When I got around to checking it out it worked fine. Later it quit. It would rotate the turntable, load up a disc when you hit play, try to play the disc, fail, go to the next disc, etc. I pulled the cover, watched it try, could hear the lens seeking focus but the spindle wouldn't kick in and rotate. After cleaning the lens with no luck, my teenage observer decided he would spin the disc himself and maybe faster would help. Damn, if it didn't work. Sort of reminding the unit what it was supposed to do. However, not a permanent fix, 'cuz periodically it would forget and quit again. I would repeat the drill, basically giving it an assist to rotate the disc (clockwise), (maybe a few times) and it would be back functioning.
I have found the problem occurs if I leave the unit on too long, (especially in pause mode ie disc spinning, for a day or two). So I now power off when I'm thru playing discs.

Just went thru the drill again today, cover off, a little nudge to the spindle top when the disc loaded and back in business. Came to FixYa to see if anybody had an answer.

BTW, you can tell if the disc is playing correctly just by watching the track clock on the display.
Too bad the unit is so big 'cuz that means one is always stacking stuff on top of it.
Finally, and it's not like I haven't entirely dismantled this thing looking for an answer. Inside my unit is my long note on how to disassemble the mechanism.