Fixes a longstanding issue that the audio DMA engines, once started, continued to run freely after baseband::shutdown() was called. It wasn't as much of an issue before PR's #1982 and #1987 because all background processes were starting both audio-input and audio-output DMA engines and letting them run forever.
This issue was causing the Microphone app to crash when switching between baseband processes that perform DMA operations in different directions.
Fixes a longstanding issue that the audio DMA engines, once started, continued to run freely after baseband::shutdown() was called. It wasn't as much of an issue before PR's #1982 and #1987 because all background processes were starting both audio-input and audio-output DMA engines and letting them run forever.
This issue was causing the Microphone app to crash when switching between baseband processes that perform DMA operations in different directions.
Fixes #1998
Test firmware available here: https://discord.com/channels/719669764804444213/722101917135798312/1219496508400078899