WROVER-B vs WROVER-IE - power consumption on boot

[iParcelBox]

I have a custom PCB design for a production product, which I flash and programme using a Raspberry Pi prior to dispatch to customers.

We have two identical boards, one with WROVER-B and the other with WROVER-IE. Both encrypt and then flash absolutely fine, but I'm finding that although the WROVER-B continues to respond as expected and we can run the firmware, make changes to config etc, the WROVER-IE nearly always just gets stuck in a boot loop. It seems to run through the initial load OK, but then starts again with a POWERON_RESET.

I suspect that this is power related - after flashing, if I connect the WROVER-IE device to a direct 5v connection rather than power it via the Raspberry Pi it always starts OK (but I'm unable to then programme it).

Everything else on the boards is identical between both variants, we're flashing exactly the same firmware etc.

My question is: is there anything different in the design of the WROVER-B vs the WROVER-IE that might require a higher voltage or current draw during the boot phase which could be causing my problem? Or does anyone have any suggestions in what I might be able to do to debug exactly what's causing the problem?