ReinardSynth#5 Top 8 of Synth faults

Looking back at 7 years of fixing more than 200 synths or related devices as a hobby, I made a top 8 of common issues with synths. This might help focussing on what to look at first when confronted with a faulty synthesiser.
Referred websites:
Schematics:
elektrotanya.com
www.synfo.nl
Online synthesiser parts shops:
www.synth-parts.com
www.vintagesynthparts.com
www.syntaur.com
Online electronic parts shops:
www.mouser.com
www.digikey.com
www.rs-components.com
S1000 Mobile Phone backlight hack:
inkoovintagecomputing.wordpre...
Replace CCFL with LED video: (The signal Path)
• TSP #78 - LCD Screen B...
Display replacement bible:
/ 240753386809789
Keyboard Switch list:
/ 1624471611029276