@ariel-m

Hello and welcome to the user to user forums.

The first thing to do is to open the clips in use in Film and TV or similar playback program to check there are no problems with the sound to begin with. That there are no static sounds or forms of distortion. It also helps if all the files share the same quality of recording such at sample rates, bit depth an so on and recorded file format. Although not completely necessary the last comment helps with the overall quality of the sound mix at the end.

Mixing sound can be as complicated as editing video itself.

There are a lot of tools within VPX and MEP to help out with this but there may be problems with using each.

First there is the track mixer slider that can be used to make sure the track volume peaks the mixer channels slider to 0 dbm when the mixer slider also is set to 0 dbm

You could also ask VPX to automatically do this for you by right clicking the audio track and selection one of the options to adjust the level. Normalize (Maximum level) should put any peak in volume to no louder than 0dbm. Normalize (EBU Ri28) uses a broadcast standard and to be honest I'm not sure what that level would be. I tend to do all my adjustments manually. The rest in the drop down menu adjust the levels to a prescribed level if you know the actual level of the recording and is useful if doing something like surround sound mixing.

The audio mixer itself has various tools to help out.

Each channel has it's own set of base plugins that can be used to control volume, alter frequency responses and compress the volume if needed.

When using any of these tools you should still keep an eye on the channels volume. You can allow the volume to peak more than 0dbm at this point but it could get more difficult to mix multiple tracks later on if it gets too out of hand. Note there is more than one preset that could be used but equally you could tailor your own if you so desire or need to.

The Master channel tools are slightly different and also includes a limiter that should allow the output not to exceed the 0dbm limit that would result in clipping and produce the static type noise you may be hearing when exported. This should always be turned on but don't rely on it to stop unwanted distortions or to neglect keeping an eye on the individual channel volumes as sudden spikes in volume could still cause problems.

You will also notice there are a number of presets for various types of audio but if you are mixing speak with music it is best left alone.

The audio master channel and the mixer channels should have two readouts at the base of each. Normally I would set the master to have an output of minus .01 if possible, just to be safe and ensure no clipping occurs to the exported video clip.

If you have any problems with an individual audio track such as clipping or wind noise or volume hiss, VPX and MEP have tools that will try to reduce the problems but don't expect results that would be as good as having a recording with no problems. The tools can be opened by simply double clicking on an audio track.

More information can be found in the pdf manual about each one.

How to balance all of this is an art in itself and has to be practiced for best results, as with everything there is seldom a one size fits all solution.

As for the laggy situation of the audio, that could just be your system struggling to cope with playing back multiple audio or video tracks at once that have to have blocks of each track preloaded into ram before playback. Sometimes adding ram can help if you have less than 16GB of it but other factors such as processor power, ram speed etc, may have to be taken into account.

However, none of that is a given without knowing more about your system, the types of files you are using and other possible variables.

Ray.