Hi
Corel Tech Support has tested a clip and confirmed that the AC3 audio component in the .m2ts (AVCHD Video) clips is not supported in Pinnacle Studio 23 under Windows 7. There is a fine print note in the PS23 specs. For AC3 Windows 10 is required.
The footage was shot with a fairly recent model Sony Handycam. The AVCHD Video files will import to PS23 but there is no audio.
So, it appears that the Pinnacle options for editing AVCHD with AC3 is to stay with PS22 or prior version or upgrade to Win 10 (if able to do so).
Tech Support will advise me regarding a refund of the PS23 cost (still within the 30 days from purchase).
Chris C