I don't think there's any problem with the patch memory. Once the EX-800 started producing sound (and I'm still not sure why it wasn't initially) I was able to go through all the presets successfully. I opened it up and checked the battery - it's in place on the main board. I didn't test it, but it looks like it's where it's supposed to be. I attached a photo of the insides.
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Re: [korgpolyex] Introducing Myself - and a question
2017-10-10 by tonsil@...