I have confirmed that sound is output from all terminals. ※ The cover for the optical terminal is missing. Please check the photos. Please be sure to check all the photos. We are looking forward to purchases from those who understand that this is a used item. Accessories Main unit Vacuum tube Remote control Power adapter USB cable Box ■ Product Description AIYIMA T8 Bluetooth 5.0 TUBE-6N3 Digital Tube Vacuum Tube Preamp Headphone Amplifier Digital Decoding IIS, SPDIF, HFP, TWS, aptX, aptxHD Supported for Home Audio Systems ・1. Tube Model: 6N3 Replaceable tubes include: 396A, 2c51, 12B4A, 5670, 6H3n-E, etc. ・2. Distortion: RCA 0.02% / HP: 0.003%, Input Modes: rca / Bluetooth / pc-usb / fiber / coaxial Support devices: mobile phones, tablets, computers, mp3 TVs, etc. This preamp does not support phono players. ・3. Output Modes: Headphone amplifier, active speakers, power amplifier + passive speakers. ・4. Chipset: CM6642 + ES9018 + OPA1656 + NJW1194 + QCC3031 + 6N3 + MAX9722. ・5. Amp Output Power: 150mw @32Ω, Bluetooth / Optical / Coaxial Sampling Rate: 24bit44.1khz / 24bit 96KHZ / 16bit192khz. Bluetooth Chip: QCC3031, Bluetooth 5.0, Stereo, IIS, SPDIF, HFP, TWS, aptX, aptxHD supported. # Audio