I used to think it was my bass, but now I've got two basses I'm pretty sure it's me.
I try to practise a little in thumb position whenever I practise the bass, just so I don't get totally terrified of going up there or whatever, but I've noticed playing pizz I get very little sustain much beyond the G, and it seems people I see on Youtube or whatever get more than I do.
Is it me? My bass is strung with Animas which seem to rumble on quite lengthily on the lower notes. My left-hand technique is pretty crap in thumb position, I feel like I'm clinging on for dear life sometimes, I don't really get how players can look so relaxed doing it, it seems to involve quite a lot of strength when I do it?