Hey, guys. This is the most pernicious bug I've ever chased down and I have to say, one of the most maddening. It took about three days of troubleshooting to get this far; prior to this I was blaming it on mLAN and actually bought $400 worth of gear to counter it. The issue is this: When I set an insert in a channel or bus in Logic 9, I get random, sporadic "pops" (1 sample triggers, I think) on any open insert. - but only on the left channel - but only if the insert is an analog signal pass - going TDIF bypasses the issue SYSTEM (bear with me) Computer Model: 2x 3.2GHz Quad-core Xeon Amount of RAM: 20 GB 800 MHz DDR2 FB-DIMM Audio Hardware: 2x MOTU 2408 Mk II via PCIe-424 card, clocked at 48kHz via Lucid Genx6 master clock (into 2408 #1). System is heavily reliant on TDIF, with monitoring via Tascam DSM7.1 (clocked via wclock). Other gear includes a Kurzweil K2500xs and Kyma Capybara 320(wclock) via IF-AE8 (clocked via TDIF), Onyx 800R (wclock) and Kurzweil KSP-8 (wclock), AES out to IF-AE8HR (TDIF) to 2408 #2. The analog outputs on 2408 #1 are used to drive a pair of Dorrough 80As. The analog outputs on 2408 #2 are used for the FX Inserts in question. the exact OS version in use: 10.6.7. the exact Logic Version in use: 9.1.1. Although thanks to this forum I discovered that keeping Logic in an Applications folder called "audio" makes it not update, so I moved it and updated it and the problem didn't go away. other audio software such as Audio Units or software: Well there's a bunch in there, obviously. However, I've narrowed this problem down to just Logic and an instance of ES1 to test it with and it's still there. I was initially coming into the KSP-8 via mLAN and thought my problem was the Aggregate Device Editor, so I ripped out the mLAN card and replaced it with an AES card, and then came AES out of the KSP-8 and into the IF-AE8HR (purpose-bought) and out of that into the TDIF on 2408 #2. So I spent about $450 trying to fix this problem and it didn't go away, much to my consternation. * * * So basically the problem is this. I've got an Eventide H3000, an Ensoniq DP/Pro and a Sony V77 that I like to use. I used to come out a channel and back in a channel to loop through these but when I upgraded to Logic 8 I started using them as inserts, which worked dandy. No pops, no nothing. Then I upgraded my system from Logic 8 on a dual 2.5GHz G5 to Logic 9 on the 8-core 3.2GHz Mac Pro I'm running now. I bought a KSP-8 about the same time. I used to hit the Eventide, the Ensoniq and the Sony analog with no problems. I hit the Kyma AES via TDIF with no problems. I hit the K2500XS via a KDFX via TDIF no problems. But as soon as I upgraded to the Mac Pro, ver 9 and the KSP-8, I discovered these pops. Here's the stupid thing. I *only* get them on the analog outputs to the Eventide, the Sony and the DP/Pro. I do *not* get them to the Kyma, I do not get them to the KSP-8. I *did* have to upgrade from a PCIx-424 to a PCIe-424 when I did that; however, I've done a fair amount of chasing so I don't know if it's the MOTU card or not: - It's the left channel only, always (shows up on the channels with the inserts) - The more open analog inserts, the more pops and clicks each channel gets - It seems to simultaneously fire 1-2, 1-4, 2-4, 1-2-3-4, 1-2-4, 1, 3, but never just 2, never just 4 - I've replaced the firewire cable to no avail - I've changed the port I'm using on the 424 card to no avail THINGS I'VE TRIED IN LOGIC: - Changing from 32 bit to 64 bit and back (no change in either mode) - Changing I/O buffer size (no effect) - Changing process buffer range (no effect) - Changing Re/Wire behavior (no effect) - Changing plug-in latency (never goes away, although compensation off seems to speed up the hits) - Changing to low-latency mode (no permanent change, although setting it to low latency paused the hits for 15 seconds?) - Turning off 24 bit recording (no effect) - Turning off software monitoring (no effect) I'm not getting any of this in Cuemix Console, MOTU's native app for patching and repatching within the 424 card. And I'm pretty well at my wit's end. I'd love any input or advice.