Hi Marshall, to me it sounds like a timing problem, and might need to be taken to a machine repair shop for a tune up.
It sounds like you have covered the main issues, but here's a list you can go through, item by item to see if you really have and aren't missing a little yet crucial thing:
https://help.brother-usa.com/app/answers/detail/a_id/76369/~/machine-will-not-pick-up-bobbin-thread The list is from Brother, which doesn't make the White, but the basics are universal. You'll need to check your manual to find out which bobbin is correct, and for any other specifics.
Check your upper thread tension. Too tight causes it to pull back up instead of letting the bobbin "catch" it.
Marshall B.
HI i am Marshall B.
i have a White 3300 i just got from ebay and when i first got it it worked fine. Now, i can't get it to pick up the bobbin thread. I have tried everything i changed the needle, thread, bobbin thread and even new bobbins. i have tried to use stabilizer doesn't work. i changed the material two or three times NOTHING!!!!! i am at my wits end with this machine. i am ready to throw it out. Could someone maybe give me some suggestion's as to what to do???? i have cleaned everything i could with caned air and with a cloth by hand and it still will not pick up. I am an accomplished sewing machine usser but this machine is baffling me i just don't know what to do.....