Ynis - AFAIR Holland & runeight have been very good at pinning down issues in CTH to particular part(s), but I think they may be unavailable ATM.
Having had issues way back in my proto PCB build, and having incrementally replaced targeted components to no avail, as the parts are available & inexpensive in the US I choose the shotgun approach
. I needed the amp going for a meet & couldn't fiddle around.
It seems to me one buffer is locking up & dumping voltage directly to output.
Assuming you've assured all the correct components were installed in the correct places w/the correct orientation & there are no shorts
, just to be clear, what exactly are your measurements for all of the following
# Measure between OG and SG. This should be very close to 12V. If it's not there might be a problem with the TLE2426 or with one of the devices in the rail splitter.
# If the OG measurement is good, measure OL and OR (with respect to SG) . They should also be very close to the voltage at OG. If they are the buffers and splitter are working.
# If OL and OR are not close to OG (>50mV), then either the buffer opamp is not working or one or more of the buffer BJTs are dead (or the wrong hfe class - not possible if you've Bill's kit). IOW, what are your OL <-> OG & OR <-> OG voltage measurements?