The 1.87 update fixed all of my dropout issues - coax & opt.
I haven’t revisited the dropout issue ever since I bought an HDMI to coax audio de-embedder, and it has been passing the audio signal to my D90SE from my SACD player flawlessly. Now that you’re telling me that the firmware somehow fixed this (I thought the issue pertained to the input receiver on the Topping and was firmware-independent), I’m wondering what the difference in performance quality I would see if I ran the coax out of my SACD player to the D90SE directly without the de-embedder.
My instincts tell me that digital is digital and that there shouldn’t be a difference in audio quality. However I’m inclined to stick with the de-embedder because per Sony’s licensing rules, all SACD players (except for PS Audio’s) are required to down sample SACD signals from DSD 64 to PCM 48khz/16 bit via digital outputs—HDMI being the exception. I’m getting PCM 176 and 24 bit output to my Topping via the deembedder.
PS Audio apparently made some deal with the devil with Sony to circumvent this—their PerfectWave SACD player is able to transmit unadulterated DSD signals to their own DACs. That is the only exception I’ve found anywhere, and PS Audio boasts about it on their webpage.