Tone Board Playing One Channel Only

[Spikerguy]

Already replied on this Thread

Tone Board Only Playing One Channel

I recently purchased a TB but it is only playing one channel. I have connected it to a PC and Pi with the same result. It is not the amp or cables. I can play stereo using a Pi with a HiFiBerry Dac+ Pro connected. The firmware has been updated but no change. Is there anything else I can try or should I send it back for a replacement?