I've noticed that when I'm running a pattern, while it plays/sounds fine, I get a little bit of lag on the bar counter. Granted, some of the patterns can be a little dense, which is what I imagine is causing the problem.

It's not really a big deal until I want to pair up with my external drum machine. It seems like the BPM can slip up a little bit.

Anyone else notice this problem? Any thoughts?

midi sync on 606 is not really good.....

I don't actually mean MIDI sync, rather just playing the two alongside one another.

So you're not using the SP606 as a master & using the drum machine as the slave/set to play on receiving the play note (or vice versa)?

Any kind of slowdown on one machine will affect the performance/recording & unlike a real musician won't compensate for the blunder & get back in time.

If you midi the two together you should get them working in time.

i had noticed that the first time i bought an sp606.
while i played 2fx+roll+scrolling patterns the latency was there.
i hope this will not be repeated with my new 606...