The search returned a dozen PDFs, all in broken English, all for slightly different models. But one link stood out: a forum post from 2012 titled “ROHS recorder won’t play — unless you know the secret.”
The file erased itself. The ROHS recorder went dark.
The secret, according to user “TapeLoop47,” was that this recorder didn’t store audio on an SD card. It stored it in that only activated when you held REC + PLAY + VOLUME DOWN for exactly seven seconds. Then, the last recorded file would play once — and self-delete.