Low Latency Monitoring Bug???

[asoemo]

Hello there,

I'm having some very strange issue with LLM in Pro Tools 9. In very specific instances the LLM button has absolutely no affect on input latency. the output of the track is going straight to the main outputs as it should. It has nothing to do with the Delay Compensation as I can recreate this problem with it on and off. Essentially what i have nailed it down to is when I am using certain buses, LLM stops working. as soon as I stop using that bus, LLM works perfectly. The thing that is very confusing about this problem is it isn't the same bus that causes the issue in every session. I think the problem may be related to the I/O settings but i can't seen to see any difference in the sessions that have the problem and the ones that don't.

For instance in one session if bus 1-2 is being used LLM won't work. When I disable it (the input on the aux track), LLM will work fine. in a different session, LLM won't work when Bus 31-32 is in use but will work totally fine with bus 1-2 being used. Very frustrating...Killed me in a session yesterday while trying to lay in some bass on a session with a ton of VI's and plugins. I couldn't get the buffer settings low enough without throwing up errors. I can't stop routing signal just to get LLM to work. Would love some pearls of wisdom if anyone has them. thanks!

by the way, i did a search and couldn't find much. Found one other person with this problem but they posted in the Pro Tools 8 forum so i figured we would get a discussion going in here. thanks again.

oo

[KingFish]

Do you have a Master fader on your session? If So, make it Inactive... does this still happen ?

[asoemo]

In the sessions that I have recreated the problem they have master faders. I have a few actually. One for the master output as well as a few for internal buses. I will see if disabling the master faders has any affect but in my other tests, i could get it to stop without disabling the master faders and even if the master fader of a particular bus was affecting it, the master fader for the main outs would still be in the session.

why do you ask? Have you heard of this problem before? i will do some tests and let you know. Thanks for the reply.

[KingFish]

Well I just know that if theres a Master Fader in your Session, across your Main Hardware outputs, then, tracks assigned to your "Main outs" are actually assigned to the "Main Fader" before it hits your Hardware.

Any Delay being compensated for, on your Master Fader, across those outputs, will also effect any tracks you're routing to your Main outputs.

I never record with a master fader active, reactivate it for playback, when the recording is done, but have encountered latency problems, having an active master fader in the session that were alleviated by deactivating it, while I recorded.

[asoemo]

Okay...I have tracked down this bug and can recreate it every time. here's how:

Create New Session
Create Mono Audio Track
Create Stereo Aux Track
Set input to Aux track to any bus
Using a send to send signal to that bus
Record Enable Audio track with LLM enabled

As long as there isn't a plugin on the Aux channel, LLM won't work on the Audio Track when record enabled. Simply insert a Trim plugin onto the Aux channel and LLM will work fine. This will work without even turning the send up. If you "Make Inactive" (not bypass) the Trim plugin the latency comes back right away. "Make Active" the trim plugin on the aux and the Latency goes away.

The reason why i do this is for parallel processing drums in the session. One of the aux tracks has nothing on it and the other has processing. The problem happens even when the Aux input has nothing to do with the routing of the channel being recorded. Very strange...

by the way this has nothing to do with Master Faders. This can be recreated without a Master Fader in the session.

[Kanosan]

This is also happening to me and I don't have any aux tracks in the session. Just mono and stereo tracks and a few instrument tracks all going straight to Out 1-2. Anyone else having this issue? I'm running PT9 on Snow Leopard with the new Avid Mbox Pro.

[Music Guru]

I'm having the same problem. 002R with PT9, Low Latency Monitoring doesn't work as it should.When selected, it has no affect on the input signal. A day ago I was using PT8 and it was working fine. I'm doing a fresh re-install off 9.0.1 plus the drivers so I'll report back. I hope someone finds a solution to this quick. Avid?

[DigiTechSupt]

This is a known issue and is in the queue for a fix.

The problem is that only Audio tracks are working with LLM - Instrument and Aux tracks do not.

[chroma17]

I am also having this problem, but it IS happening on audio tracks. However, it is only happening in certain sessions. I have one particular session where LLM was not working on any audio track. I tried to create a new blank session and import all the tracks from the old session and the LLM bug appeared in the new session. I fixed the problem by creating a new session and importing the tracks WITHOUT input, output, or send assignments. This time, LLM worked properly in the new session. I am pretty sure the new "New Track" feature in the output routing contextual menu is causing this.

To reiterate, the problem was happening on audio tracks which were routed directly to the main output, as well as tracks sent to busses. I was able to recreate this problem with no plugins loaded (only Stereo Mixer in the plugins folder) This was only happening in one or two sessions...if I create a new session LLM works properly. Problem happened on PT9 and 9.0.1, 10.6.4 and .5

PT9.0.1, 10.6.5, iMac Core 2 Duo 2.8Ghz, 2Gb RAM, FW400 session drive, MBox 2 Pro

[chroma17]

I just verified this...
Creating an aux track and bus via the "New Track" command in the output page breaks LLM in the session.

To reproduce:
1. Create Audio Track
2. From output assignment menu, select "New Track"
3. Create a mono aux track in the prompt that appears
4. Create a new Audio Track
5. Record-enable the new track

-LLM is now broken-

To fix:
Set the Aux Input you created in step 3 to "no input"

LLM works again immediately

I just did this in a session with no Master fader, so that doesn't have anything to do with it. Also not a plug in issue. See computer specs in previous post.