Clicks and pops when tracks are assigned to FX-channels

[caLRo]

The clicks and pops appear when playing a project that has a few instances of Synth1 VST and some drum samples. All of them are assigned to a separate FX-channel, the faders are at 100%, and all are sending to the master channel only.

I've already checked each track to see if "envelopes with 0 attack" were the cause, but that's not the case. Also none of the tracks had high volume and were not clipping.

Then I decided to unassign each track from their FX-channels and the pops and clicks were gone. Is this a known issue, and is there a way to solve it?

Win 8.1 x64
LMMS 1.1.0 64 bit
SDL

[caLRo]

Update

I've tried a few things to further isolate the problem. It seems the clicks and pops appear when any VST is loaded with VeSTige and assigned to an FX-channel. When not assigned, there are no clicks or pops. The problem persists after lowering the send value of each FX-channel from 1 to 0.9.

I can replicate the problem by creating a new project, loading a few instances of VeSTige with a random VST (so far I've tested with Synth1 and a few DSK VSTs), and assigning each of them to an FX-channel.

So the problem seems to be in the area where VeSTige interacts with the FX-mixer. Am I wrong? Please help.

[musikbear]

looks nasty..
You already have the best settings, and you have also isolated the issue
No, if this is a fact, then you have found something, that needs to be fixed..
One Q :
When you hear these click/pops, what does the cpu-indicator show? Is there a short peak?
Do you use auto-backup?
If you do, disable it. It is a serious cpu-hog, especially if you save larger projects.. (and will be changed, at some time)
-but is that relevant here?

Last idea for a 'fix' is to downgrade to x32 ver. of lmms 1.1. Annoying, i know that, but x64 has some temper, in respet to the hw it runs on..

Please report back, if any of this works, because it is perhaps useful for others to know. (it is to me : )

[caLRo]

Big projects may cause the indicator to display a few green and yellow squares, but in this case there are none. With a core i7 3630qm 2.4ghz, I'm fairly confident it's not a CPU issue. I also do not use the auto-backup feature.

I can live with these tiny clicks and pops as long as I can render the song without them. To my horror, they were rendered as well.

[caLRo]

I've tried Oleg's suggestion of using ASIO as described on this thread viewtopic.php?f=7&t=1607

The replaced libportaudio-2.dll gave me two backend options, ASIO and Windows WASAPI. I've tried both and both have clicks and pops. This leaves me to think that the problem lies with VeSTige and FX mixer, and the interaction between them. In projects that have no instances of VeSTige there are no clicks and pops, even when tracks are assigned to FX channels.

[musikbear]

please read: http://lmms.io/forum/viewtopic.php?f=7&t=1608

[tresf]

Update

I've tried a few things to further isolate the problem. It seems the clicks and pops appear when any VST is loaded with VeSTige and assigned to an FX-channel. When not assigned, there are no clicks or pops. The problem persists after lowering the send value of each FX-channel from 1 to 0.9.

I can replicate the problem by creating a new project, loading a few instances of VeSTige with a random VST (so far I've tested with Synth1 and a few DSK VSTs), and assigning each of them to an FX-channel.

So the problem seems to be in the area where VeSTige interacts with the FX-mixer. Am I wrong? Please help.

Please file a bug here:

https://github.com/LMMS/lmms/issues/new

We'll take a look at it and hopefully determine the cause.

[tresf]

This leaves me to think that the problem lies with VeSTige and FX mixer, and the interaction between them. In projects that have no instances of VeSTige there are no clicks and pops, even when tracks are assigned to FX channels.

I tend to agree. Please file a short description of how to reproduce here: https://github.com/LMMS/lmms/issues/new

We likely missed this when testing the new FX mixer. Thanks for the detailed testing and reporting. Let's get it on our tracker so we can patch it.