Testtone runs well, sounds clear, has 1kHz. But if I change app to sid synt, and play something on keyboard it sounds strange. In sounds.mp3 I’ve attached recording which contains 6 ocataves played from low to high.
LCD: you considered the 4bit interface (D0-D3 should not be connected)?
LCD interconnection test done?
Strange Sound: it’s interesting that the waveform and volume (or ADSR setting?) changes while you are playing different notes. It could either be a powering problem, connection problem or firmware upload problem - hard to diagnose via remote, but let’s start with the power problem: does it also sound so strange when the LCD (and especially the backlight) is *not* connected?
