Regarding the sound quality issues: ① Capacitor repair is recommended, and due to over 10 years of aging, please understand that this item is being sold as junk with no claims accepted. There are two main issues, as detailed below: ① and ②. ① Deterioration of electrolytic capacitors due to aging • Phase margin ↓ • Feedback stability ↓ • → High-frequency oscillation folds back into the audible range Is it safe to use as is? Short-term: ○ • Won't break immediately • No risk of electric shock Long-term: × Not recommended • Constant slight vibration in speakers • Increased high-frequency distortion Realistic solutions: Overhaul (best) • Replace all electrolytic capacitors • Worth doing for a 15-year-old unit ② The physical power button's contact is weak due to aging, so remote control startup is recommended. Product Name Pioneer VSA‑830 — Pioneer VSA-830 AV Amplifier (5-channel AV receiver)  AirPlay compatible ⸻ Basic Specifications Sound Performance • Type: AV Amplifier (AV Receiver)  • Number of channels: 5 channels (supports up to 5.1ch)  • Output: • Rated output: Approximately 95W/ch (8Ω, 20Hz-20kHz, THD0.09%)  • Signal-to-noise ratio: Approximately 100dB (line)  • Speaker impedance: Supports 6Ω to 16Ω  Video/Connections • HDMI: HDMI input/output available (4K passthrough supported)  • Digital input: Coaxial/optical/LAN etc. supported (varies by model)  Functions/Supported Formats • Dolby/DTS: Supports decoding of Dolby TrueHD, DTS-HD Master Audio, etc.  • Network/Wireless: Wi-Fi, Bluetooth built-in (supports music streaming)  • Sound field correction: Equipped with Advanced MCACC automatic sound field correction function (dedicated microphone included)  • USB/Media playback: Supports high-resolution audio playback from USB port (FLAC, WAV, etc.)  Physical Specifications • Size: Approximately 435 × 168 × 331.5 mm (width × height × depth)  • Weight: Approximately 8.7 kg  • Accessories: Remote control, microphone, etc.  ⸻ - Brand: Pioneer - Model: AV Amplifier - Connection terminals: HDMI - Operation buttons: Physical buttons - Design: Black Thank you for viewing.