Jake’s always applied with brake pedal

[Brookhaven66]

Insite doesn’t show its active, or at any % but always shows switch “on” even when it’s off, although while driving switch will turn Jake on or off.
It believe it’s Jake,if you press accelerator to 1500rpm then hit brakes it sounds exactly like Jake,but at idle just sounds worse I think. Can’t imagine what else it could be.
This has been happening since he bought 3 weeks ago.
No help from seller.
Really odd that even on accelerator when you press brake pedal the Jake activates.