I use Adobe Audition but have also 'played' with Audacity (very good freeware/open source) in the past when I used to do IT support. Both of these can extract audio from your video for manipulation and the result can be reintroduced for final rendering. As long as you take care to preserve the length of the audio, it's very easy. I don't know about 3rd party software integration into PD - something I've never needed to investigate.

The only audio editors that feature round trip editing in Powerdirector are the Cyberlink AudioDirector and the Cyberlink WaveEditor.

All other audio editors you have to work on the audio file separately then Import the edited file back into Powerdirector. Carl312: Windows 10 64-bit 8 GB RAM,AMD Phenom II X4 965 3.4 GHz,ATI Radeon HD 5770 1GB,240GB SSD,two 1TB HDs.

I use audacity every time because it has far more capabilities than either editor attached to PD13.
It simply means you extract the audio into audacity do all the editing you want.
Export it as a wav file into the file folder you are using with PD then import it into the media library and then drag it onto the timeline. Bingo!
I also find it much better for recording Voice overs etc. exporting and importing in the same way.

Many of the functions in Audacity can be installed into both Wave Editor and AudioDirector using VSTs, loads of which are available for free on the internet.
Granted it would take some homework, but you'd get your round-trip editing. HP Envy Phoenix/4thGen i7-4770(4@3.4GHz~turbo>3.9)
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Hey guys, every time I open up my old PD11, I get a banner urging to upgrade to PD13. so today I decided to finally click on it to see what was new. Much to my chagrain, it looks like Cyberlink has taken out Audio Director from the lower-cost versions and now you have to splurge on the high-end Ultra Plus package if you want to perform audio editing inside PD. Is that right? Has no one else found this to be a troublesome change in strategy? It's not like Audio Director is the cat's meow, but it was certainly better than nothing....

In regards to Audacity, I have used it a few times when Audio Director couldn't do what I wanted but yes, it was a bit more cumbersome to use. BTW what is Wave Editor?