efiniracing

I have a Sony ES 10 disc changer, and quite often when I get in the car and try to play a cd the head unit tells me that the cd changer needs to be reset. So I have to eject the cartridge then put it right back in then it will work. What could be wrong? could it be the head unit?

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93 silver fdw/ street port & 3mm seals ,intake
pullys, blueprinted turbos, XS front mnt ic, Crane hi-6, Vitek plug wires, and hoses, trust anti sway bar front & back, pfs pms, shift light, boost guage, turbo timer, air, h2o, oil temp. guages. custom carbon fiber dash for console, e brake, shift ****, G force, optima yellow top relocation. lowered 2" w/ RE body kit & Mazda speed wing, Es head unit w/ ES cd changer, Clarion EQ w/ joy stick, 4x Mb Quartz 6.5s, 4xMb Quartz tweeters, Soundstream 5 channel amp-polished, folia tech gas tank lid, cusco fuel pump, efini badges, custom EFINI tag, 330 dyno, 12.1 best 1/4 mile.