Exactly the same issue here, and the same solution. I do have contacted Kali Audio support and they suggested to send them back.. haven't do so yet, cause I like the sound so much. Seems like the speaker wake-up/sleep signal threshold is way too high to work properly.
Supposedly, there is an internal jumper that disables this annoying "feature". Check YouTube for a video on just that.
The sound that Kali LP6 offers to budget oriented musicians deserves praise. If Kali audio can make a less noisy IN8, it will be my next and possibly last upgrade.