365 534 may still have dynamic braking enabled as it was in this video from a few weeks ago:-
However, it also depends on the driver if you hear the dynamic brake - if he releases and reapplies it too much it often cuts out.
The special announcements are all available from the site below:-
Contained within is a collection of PIS announcement sound samples from a class 365. A template ScenarioScript.lua file is included to get you started and in the ReadMe is a link to a video tutorialalanthomsonsim.com
You will need an account to download.
Just hopped on the 1P52 1828 to St Neots yesterday from Stevenage, 365520 has dynamic braking too, although one end of the train doesn't output any sound at all! (Even accelerating!) I found that quite hilarious.