YAMAHA EOS B900 Tetsuya Komuro Model [Includes Original Manual and Songbook]

[Price Reduced] This is the YAMAHA synthesizer with built-in speakers, the EOS B900.
This is a legendary machine from the 1990s, characterized by its powerful sound produced under the direction of Tetsuya Komuro.
I purchased it used (for ¥15,000) in September 2024 and also bought the manuals separately for ¥3,000. However, I am selling it because the operation is difficult and I cannot master it. I have only turned it on a few times since purchasing it.
[Operation (Please be sure to check)]
It powers on and produces sound, but the following issues have been observed:
• A specific key (C8) may not stop sounding. (This can sometimes be resolved by turning the power off and on again or through operation, but it will be handed over as-is.)
• The operation buttons below the LCD (such as the F1 button) may be unresponsive at times.
• Song data from a previous owner remains on the unit.
Due to these quirks, this item is being sold as-is (assuming maintenance is required). We ask that only those who understand the characteristics of an older model and can utilize it for repairs, parts, etc., make a purchase.
[Accessories]
The rare genuine manuals purchased separately recently are also included.
• Main unit
• Power cord (directly attached to the main unit)
• EOS B900 Owner's Manual
• EOS B900 List Book (Sound/Pattern List, etc.)
[Condition]
• As this is a used item, there is some age-related wear and minor scuffs.
• The LCD display is functioning normally.
• Output from the built-in speakers has been confirmed.
*As I do not have specialized knowledge, I cannot confirm or explain detailed functions.
*We cannot guarantee all functions.
*As this is a precision instrument and an old item, returns and refunds cannot be accepted. Thank you for your understanding.