It powers on but does not function. For those who can repair it, or for parts, how about it? Thank you. MDR-XB70BT B (Black) Brand: SONY Wearing style: Both ears, integrated left and right Earphone/Headphone type: Canal type, Neckband type Construction: Sealed Color: Black Wireless/Wired connection: Wireless Earphone/Headphone features: Microphone Low-frequency range (Hz): 4.0 Hz High-frequency range (kHz): 24.0 kHz Wireless standard: Bluetooth Wireless function: NFC Bluetooth version: Bluetooth 4.1 Bluetooth codec: AAC, SBC Drive method: Dynamic type Driver size (mm): 12.0 mm Charging terminal: USB Charging time: 2.5 hours Weight (g): 43.0 g