SACD Player Won't Play Hybrid SACDs


A few years ago I purchased a used Sony SCD-C555ES SACD changer. I bought it to use essentially as a CD player run through an external DAC. I have about 500 redbook CDs. A couple of days ago I bought my first SACDs and began playing them. Everything worked fine until tonight. For some reason, the same SACD hybrids that played fine several times will not now play in SACD mode. I get the message "Not Hybrid" and the player defaults to CD mode. I toggle between "Multi and 2 channel" and I get the message "Not SACD." Any ideas?
jjpeepers
Not an uncommon problem with the older Sonys. The laser could need an alignment. I believe there is a diagnostic procedure for doing this. Check around the web. I found this-

Resetting Operation at Power ON
If the power is turned on with a disc loaded in the set, a sequence of operation as shown below will be performed.

(The operation varies depending on the type of disc) Condition: continue mode
1. Sled reverse move (sled in)
2. Disc detect
3. IC setting for SACD
4. Servo error signal offset auto adjustment
5. Spindle kick for LD on
6. LD on
7. Focus search
8. Focus servo on
9. Spindle kick
10. Spindle servo on
11. E-F balance auto adjustment
12. Tracking & sled servo on
13. Focus bias auto adjustment
14. Focus servo gain auto adjustment
15. Tracking servo gain auto adjustment
16. Jump to lead-in area
17. Read TOC
18. Auto play (track No.1)
Thanks for the info, Chayro. I wish I knew what it all meant. However, I'm certain the problem is not an alinement or cleaning issue. Over the past few days I have done some "testing." When the player has been turned off and sits over night or is turned off for a while, cools down and turned back on, it plays fine for a while. It correctly reads any combination of SACD and CD disks that are loaded into the changer. However, once the unit is on for period of time (give or take 2 hours), it stops reading SACD and will only read the CD layer. It won't stop reading SACD midstream during a disk play. Once it recognizes SACD, it will play the disk to completion and then stop SACD recognition on subsequent disks.
A few yrs ago, the unit was modified by Matt Anker of SACD Mods. He said the unit would run warm and it was normal. The unit played fine until recently so, I don't think the problem is related to his mod (which had nothing to do with the actual disk layer reading). I tried to locate Matt just to run the issue by him, but he is no where to be found.
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On my sony 5400, you can only play sacd in sacd mode with the internal dac. The digital output only works with redbook.