I forgot
The annoying Master Caution with single chime every few seconds...
check the FMA for a THR LK. Then the PF has to set thrust manually. Cautions don't stop till he moves the levers. If Captainis PF and does not take over thrust control, tell him to do it until he realises thrust is manual now. Surprisingly, many refuse to accept that fact and just ignore it. I wonder why...