Error 1429/ stuck on "Connect to your Computer"

Hello all,

I’ve combed through the answers but haven’t found a specific solution:

iPod 5th generation, replaced battery and HD with iFlash Dual (one 128gb SD card in slot 1). Tried restoring on Windows 7 and on MacOS with iTunes—each machine gives me the error 1429.

Unable to access disk mode or diagnostic mode, as every time I reboot the iPod, the screen immediately goes to “Connect to your Computer/Restore with iTunes”.

Tried formatting the SD card several ways—NFTS, FAT32, MacOS Extended, ExFAT—all give me the same set of problems.

Any ideas? Thanks so much!!