hi there, just read here:->
„it seems that there is already an MCU fitted (ST’s STM 8S103F3) programmed to allow access to some of the es9028 internal hardware functions (volume etc)…“
guess on the „newer“ ES9028Q2M´s (layout „2017 04 09“) there is this STM 8S103F3 and there is also a 4 pin header (5V+, SWIM,GND, Reset) to program/read out them..(SWIM-interface)
so, now is the question if someone has ever read out that eeprom (on these boards) or re-programed (and with what ?)..
any comments here concerning this topic are really,really appreciated !!
(SWIM->ST-Link-Raspberry Pi->http://kuku.eu.org/?projects/stm8spi/stm8spi )
for this ES9028Q2M:
the working dtoverlay in config.txt is fortunately again (Raspberry Pi+DietPi+other):
hifiberry-dac -> (in config.txt): dtoverlay=hifiberry-dac
up to 384khz with no problem..
(rpi-dac works too, but as said limited to 192khz)
Hint for squeezelite-command-line options (also in picoreplayer->squeezelite-settings): try to use 24 (bit) and mmap on (1)..
(on this board 16 (Bit) causes only a heavy distorted noise/very often/almost in every case, beware !!))
PiCorePlayer->„in Picoreplayer you have to change from „simple/generic es9023“ (es9018k2m) to „ES9023“ (without anything)->up to 384khz;
(also had problems playing in 16bit->distorted noise; so try to use 24 oder 32 bit in „ALSA-Params“)
RPI-Dac was also possible in picoreplayer (but only up to 192khz)“
link+further description here: