Ill put it in easy words for you to explain the situation. For a shopkeeper in Pakistan, branded stuff has lowest margin, chinese or korean stuff has great margin while replica or fake has most margin. All focus on the later 2 for people who don't knoe much about car audio.
My suggestion is to get a kenwood or pioneer dvd hu if your budget permits even if its used but in good nick rather than spending on delson, rockmars, and whatever chinese crap there is in the market.
The headunit is the source of the signal so once you have a good hu you have a good signal. Take it from there and then change the equipment
Hope it helps
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