Hi
I have the same problem with my NX200, sometimes it can take 7 to 8 starts to get the stereo working. Lexus service check it out and tells there is a fault in the amplifier. A new Mark Levinson amp will cost about $1800 installed. On e bay an amp is about $1000 us. There are no Mark Levinson service centres in Australia there might be a stereo tech who can try to fix the amp
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