Then I think it can be indeed the discs themselves with problems. It could happen sometimes that just few disks to have some issues due to the materials used... so not something that could be seen in an quality check, at a larger scale, but just very few pieces.
Maybe also further check, cause I had read (some time ago) some weird manifestations sometimes, with some specific models of TV's combined with some specific models of players (usually from different brands, so if you have both from Sony, might not be the case, although I think some of the most prominent issues were with Sony TV's I think, if I recall correctly).
What I saw there in your pictures lead me to think that either this could be as you said (problems with the disc), but also could be some issues of "handshake" between the devices in the chain, especially if you also get complete dropouts of video (black screen) and sound (no sound), not both at the same time or both at the same time. But again, this kind of issues could happen mostly when there are some devices incompatibility, longer cables (especially non-certified ones), or even a faulty cable (even one that is just 1 meter long), and more prone to happen when the source demands very high bandwidth, like when the movie is in Dolby Vision and Dolby Atmos (or HDR10+ & DTS X) and all the devices in the chain are capable, but the cable is not quite.
Hope this helps!