How to Fix a Harman Kardon AVR 132 Protect Mode Problem

I bought a defective Harman Kardon AVR 132 that goes in Protect Mode seconds after power on to see if I can fix it. I managed to solve the Protect Mode issue not knowing that there are other issues in the processing of surround modes DSP, Dolby, Logic 7 and DTS processing. I managed to fix the protect mode issue but only the 6 Channel Direct input works without issues. I didn't find a solution yet for the surround processing issue so I stick to the 6 Channel Direct input using an external 5.1 Dolby/DTS digital to analog audio surround processor and repurposed the AVR to be usable as a minimum viable product while looking for solutions.
If you have a similar problem with a similar AVR, you may give it a try, DIY and see if it works in your case.
For a more detailed instructions or tutorial, please read my blog. blog.arnbb.me/...
Product References: If you buy the products from my links, I'll get a small commission.
Digital 5.1 Audio Decoder Dts/Ac-3: s.shopee.ph/7f...
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Hot Air Gun Soldering: s.shopee.ph/3A...
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Compatible Remote Control for Harman Kardon AVR 132 : s.shopee.ph/1B...
Software used:
Capcut Ai Web for video editing and narration
Udio Ai Music Generator for producing the background music