[quote name='Len_derby' timestamp='1394640570' post='2393610']
You might be doing this anyway, but do you thread your lead 'over the top'? Assuming you play right-handed, take the jack plug in your right hand, thread it behind the bass, in the space between you, the bass and your strap. Pull it over the top across the front of he bass and place the plug into the output socket of your bass. The cable's own weight shouldn't be pulling it out now, and your strap should stop it falling sideways.
[/quote]
+1 to this