Version 16.12 was released today and is available for DOWNLOAD.
More About the New Audio Mixing
The first thing you need to know about the new mixing mode is that it only applies to new projects. You might have already adjusted volume levels in existing projects, and we did not want to affect that.
Versions before 16.10 used a mixing technique that tried to be clever about generally preserving the levels of all sources without clipping, but it was discovered that it may introduce artifacts. So, versions 16.10 and 16.11 switched to a simpler method that adds samples, but it was also averaging them to avoid clipping, which was found to adversely affect levels. So, the new approach in this version is to simply add samples.
As a result, you may experience clipping. Now, as long as there is so-called headroom in the level each of source, this should rarely be a problem because high level samples from each source are rarely correlated. Here is where the Normalize filters are your friends because not only do they bring all sources to the same level, but the default target level includes headroom. In addition to listening for clipping, you can visually monitor it using the Peak Meter and/or Audio Waveform scope in the View menu.
If each source has headroom in its level but you still experience clipping, you can add a Gain/Volume filter to the Timeline - select the cornerstone at the top, left of the Timeline and use the Filters panel. This is like the Master Out gain control on a mixing console. Reduce the gain until you eliminate the clipping. If you find that you need to lower the gain more than you like try adding the Limiter filter.