will do i2s-slave later.

adds missing IOMUXC_SAI1_RX_DATA0_SELECT_INPUT = 2;

Reverb: memset: wrong size - element size is not 1

Bugfix: Errors when using 168MHz due to missing line

Bugfix for missing initialization of data pointers in AudioPlaySdWav

If AudioPlaySdWav::block_left / block_right are not properly initialized to NULL, AudioPlaySdWav::begin() may crash, because their usage in AudioStream::release() may lead to undefined behavior.

Add missing Keywords setLowShelf/setHighShelf

Without, the whole lib does not compile with 168MHz.
--> added missing line.

Add control object for TLV32AIC3206

https://github.com/TeensyAudio/Wavetable-Synthesis

https://forum.pjrc.com/threads/52679-Teensyduino-1-42-Released?p=181195&viewfull=1#post181195

https://forum.pjrc.com/threads/50537