Sony HDPS-M1 Operating Instructions Manual page 17

Removing the "Memory Stick" media
Note
Never remove the "Memory Stick" during copy. Otherwise, data may be corrupted.
Push the "Memory Stick" all the way in, briefly release it, and then
pull it out.
When you push the "Memory Stick" all the way in, it slightly sticks out.
Push in
Release briefly and pull out
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