The best replacement for i2s is i2c.

The best alternatives to i2s are rated as following:
★★★★★  i2c
★★★★  pcm
★★★  spdif
★★★  spi
★  left justified
★  ac97

Your alternative for i2s is not listed? Suggest!
Speaking about i2s, one probably shouldn't forget about pic32.

Other search terms related to i2s and their ratings are:
★★★★★ pic32
You have in mind a companion for i2s and it is not yet here? Propose!



Google Trends

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i2s
i2c
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