Macbook 1.1 will not boot from "power off" with SSD

I recently installed an SSD* into my MacBook 1.1 and am experiencing a strange phenomenon when starting the computer from an unpowered condition. *SanDisk SSD Plus 480 GB

The SDD sucessfully restarts the MacBook when selected in the "Startup Disk" module in System Preferences.

Restarting after pressing the power switch also works fine but it does not start-up after being shut down (powered off).

When powered-on again, a question mark flashes and the MacBook will not boot.

If the original HDD is connected by USB it boots normally, and then shows the SDD available at root level.

If the "option" key is pressed after powering-up, nothing happens if the HDD is not plugged into the USB.

With the HDD conected via USB and the "option" key pressed during power-up, I am only able to select the HDD. (The SDD is not shown.)

With the SDD running as startup disk all works well, even with the HDD disconnected and after reactivating it from sleep mode. It however loses connectivity to the SDD when powered off and will not reboot without reconnecting the HDD via USB.

Does anyone have an idea how to solve this problem?