My speakers almost exploded!!!
I did some more experiments with different devices.
What I can say that it happens with pure analogue amplifiers only. Checked with an "Atoll AM300" power amp -> huge blast. "HAIKU AUDIO SOL III Powerstage" -> same huge blast. "Advance Paris BX1" -> again that same huge blast.
I suppose it might have to do with speaker protection mode triggered from their own amps' chipsets (Infineon Merus). That could be the reason why that flaw wasn't detected by them when that broken firmware was tested. Issue got covered-up, so to say.
-> To be specific, if hooked up to Infineon based SMSL amps (like A300) or Sabaj amps (A20a, old 2020 version) there was no such blast in both cases. Did a lot of testing today with these devices.
After all that testing what I can say that the "blast" coming from my speakers or headphones isn't as unspecific as I thought initially. (So not like capacitor discharge or related kind of "blast").
Depending on how a track starts (e/g drums hitting or just some backgroind noise) it seems to be a simple matter of
"full throttle output" for roughly 1/5 of a second from that DAC. Tracks starting with backgroind noise still sent a significant blast to my speakers or heaphones, while tracks with drums hitting at first second it was just unbearable and potentially equipment-damaging.
@SMSL-Mandy how about that? Did you do some more assessments?