I'll look into these issues. There are measures already set in place to fix this, but it seems to not be working anymore. I might not be able to do anything about the sound issue, I believe I can but there are some sounds that Valve refuses to let us mute. Perhaps h3bus was able to resolve this issue already and it's an easy adjustment. As for the pistol swap, I am not sure what is causing that as I've not seen a report about it nor had a complaint about it on my servers, but if you can find when and what might cause it, let me know please.
h3bus also had dm_fast_equip where people equip the weapons without the animation. It'd be awesome if you are able to add this feature.