Faulty Decorder from DSTV on contract no one is helping

As a DSTV subscriber who opted for a monthly contract with a DSTV Explora decoder, I've encountered persistent issues with recording and rewinding shows since receiving the decoder. Despite contacting Multichoice multiple times, they insist there's no fault with the decoder. However, my older PVR Explora decoder functions properly, raising concerns about the quality of the new decoder. As I'm bound by a contract, I'm unable to cancel the service, yet DSTV has not offered a satisfactory solution while continuing to bill me for subpar service. I'm requesting DSTV to replace the faulty decoder promptly; otherwise, I'll have to explore further actions to address my dissatisfaction.