HV40 Import to FCPX Archive - Stutters with older SD tapes - PLEASE HELP

Hi everyone
I need help. I have a Canon HV40 Mini DV tape camera and latest FCPX.

I am archiving all my tapes.

Starting at tape 90 and working backwards I am now down to tape 40.
This is where the problem starts all 90-40 have been totally fine as they where all recorded on the Canon HV40.

Tapes from 40 down to 1 have been recorded on a number of different camera and this is where Im hitting a problem.
First thing it stutters the video and makes a new .mov every few seconds (making lots of timecode brakes where there isn't one)
Secondly in the FCP viewer there is no sound. There was always sound on the import before on all HD tapes made originally with HV40.
These segments when tested in FCPX do have audio when played just not on import.

Another note to add is all tapes 40 down to one are now SD as they are older tapes I wish to archive.

How can I import these best with audio and without these timecode stutters?

Thank you so much in advance for any help everyone.

Try with QuickTime Pro 7 (still for sale on Apple's site, very cheap).

Thank you Ben for your advice.
After much research I got LifeFlix from app store.
I was worried I would be throwing my cash at something that would either Stutter or have a problem with sound.
Im extremely happy to announce it worked perfectly and also has no compression