Honestly, I would download free software that transfers your CDRs to high-resolution lossless files, store them on a USB flash, and play them from there.
This is the program I use; it's quite good and allows you to transfer them as high-res files.
You can store a $hit-ton of songs on a 128G stick, and they are about $15-$20.
If I recall, my DEX-P99RS has a 128G read limit so you may want to check it out on your unit, maybe more, maybe less.
You could also get one of these and just plug your phone in as another source too.
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