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Turn your old speakers or Hi-Fi into Bluetooth, Airplay and Spotify receivers with a Raspberry Pi and this step-by-step guide
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Amazon.co.jp: Hack Bluetooth Speaker, v5.1 Wireless Speaker, Luminous Speaker, Bluetooth, 20 Hours Playback, Small, LED Light, for iPhone, Android, Smartphone, PC, Lightweight, TV, Car, Heavy Bass, Multiple Connections, Black, Medium : Electronics
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