The replacement boards work fine . Up a running again

Its not the usb port. tried a new usb cable in usb2,usb3 and powered usb ports and got the same brownout fault. The second esp32 board I bought, which is provisioned as a BLE_server, works with all usb cables and usb ports.

After uploading this IDE sketch (based on BLEclient example):

#include "BLEDevice.h"

...some code...

void setup() {

//Start serial communication
Serial.begin(115200);

//Init BLE device
BLEDevice::init("THC Controller");
BLEScan* pBLEScan = BLEDevice::getScan();
pBLEScan ...