Does it exist? I hoped i would find some Android Based MP3 players without wireless and aux only… The only other options i found where some SBCs that support android like the AML-S905X-CC, but i assume its kinda finicky geting a Touchscreen working on them.
Audio Modem
So like an airgapped device? Have you considered getting a cheap off the shelf tablet and cutting the antennas? It wont connect to WiFi or BT anymore after that?
Cutting the antennas is far from removing the problem, even without antennas those chips still make a lot of noise in the 2.4ghz band. Id woud have the desolder the whole wireless chipset, i mean i have the soldering equipment for that, but i kinda doubt that a normal android will even boot after the Wireless chipset is gone :/
I think you’ve been underspecifying the problem a bit :) You dont want any 2.4ghz signals at all? Does airplane mode still give off 2.4ghz noise? Are you sure the noise is from the WiFi chip, and not the CPU?