IO and Keyspan, frame accurate?

Just finished mastering a large project to 22 digibeta tapes in PAL country. As others, I got frustrated by not being able to edit to tape frame accurate (one frame to early, on time, and sometimes up to two frames too late). Tried all the suggestions mentioned here on Cow. TC to LTC only, preroll for deck to 5 seconds etc, to no avail.

I was wondering if it is a good idea to try to bypass the IO for deckcontrol with a Keyspan serial adapter (USB>serial) and control the deck directly from the computer.

Is anybody using this together with IO and what are the results?


System: 2 x 2GHZ, 1.5GHz RAM, Aja IO, Huge Media Dual Vault 800 GB, Atto UL4D, Sony A500 Digibeta, FCP 4.5, OS 10.3.5
Note: I don't use blackburst. I connect composite out from IO to REF in on Digibeta when mastering, and vice versa when capturing

All equipment has latest drivers etc.


Niels