Thanks a lot for the advice, very much appreciated. But connections are ok, signals are ok, and the problem persitsts.
As one needs an extra board for a buffer anyway, I think it is still safer to add a buffer and DIT4096 or DIT4192.
As I unslodered my CX 23035 using the trick by bending the legs with a thin wire while unsoldering renders the CX23035 pretty useless for future use.
Not problem for me as I have another mainboard.
But here is 80 legs to be SMD-soldered against 28 with the DITs. An adaptor board can be used with the DITs as well, the rest can be bigger IC´s that
can be easily soldered.
CXD1125Q is obsolete while DIT4096 and DIT4192 are still listed as active.
My idea is to omit the digital filter, dac and uutput stage completely and replace it (connectied via SPDI) with a tiny ES9018k2m Dac with ES9601 Headphone / Line driver.
This definately sounds better than the original CX23034 / CX20152 combo. When I omit the CX23034 I have to replace the 67.7376 XTal with an Xtal of 16.9344 with :2 divider as the the DITs need this frequency.
and the CX23035 needs 8.4672. When the digital filter CX23034 is not omitted, it will provide both frequencies via pins 2 (16.9344) and 4 (8.4672).
BTW I am trying to replace the lasr diode of the BU-1. Not easy as it has a diffraction grating in the light path that has to be re-aligned. Looks like a matter of luck,
as the grating is secured by screw locking varnish. If there was enogh applied, one might be as lucky as this guy @ vintageaudiolaser:
http://vintage-audio-laser.com/A-l-atelier-page-54
scroll down to "Sony CDP-502ES - Remplacement de la diode laser"
But in my case, there was almost no varnish applied . the grating got loose what renders a replacement ueseless for the moment...
The grating is the plastic part sticking to a philips screw in one Photo. The glass in the center hole is almost invisible to the eye
