using two interfaces - sync issues?

[memes_33]

i've been thinking about this issue since i recently bought a apogee duet 2. i have always mixed OTB, using my motu 828 mkII outputs and inputs. since i bought the duet, i have been mixing: motu 828 > mixer > duet. i'm worried there is sync issues- i haven't compared the old method to the new method yet, but here's what i'm thinking about:

if my motu outputs and my duet inputs are not synced, isn't it possible (in fact, probable) that the audio information i am recording to my duet is actually the points in-between samples from my motu outputs? in other words, the sample points that i'm recording actually fall in-between the sample points that the motu is outputing, so the sample points i'm recording are actually created by the algorithm used by the motu to 'fill in' the information between the samples?

i should probably just listen and see if i can hear a difference between the (synced) motu inputs and the (unsynced) duet inputs, but i'm trying to conceptualize this shit.

[salatspinatra]

Just skimmed, but if you didn't mix on the board, sync wouldn't be your problem, latency will. Aggregate devices are possible in Audio Midi setup utility, but it's really not helpful. In your situation, I suspect you'd be dealing with gitter ("filling in between the samples" isn't quite the best concept to put your faith in, more like you're dancing under two strobe lights out of phase)-wait are you just using the Motu with direct monitoring? I'm confused. My instinct is that you would want a separate clock, but you're just using the motu as an additional i/o for your mixer, right?

[memes_33]

using MOTU for outs, Duet 2 for ins.

i'm not as concerned with jitter between the clocks as i am where the sample points are taken.