Ok. Thanks. That makes more sense.
I don't think I have ever heard two beeps coming from the DGTPi speaker before and after each move announcement. There is a menu option in System/Sound (or, if you set up the DGTPi to German - System/Toene) which you can set to 'None' ('Nie') and that will prevent all beeps from sounding (except the one when Picochess starts - which you can disable in the dgtpi.service) but it only give one beep when the engine moves, at least for me. If you set the option to 'Sometimes' ('Manchmol'), there is a setting in picochess.ini (beep-some-level) which determines when beeps occur.
As for the language in the browser, if using Safari I believe it has to be English. But, otherwise it should use the default computer language (but I never tested it myself). Perhaps someone else knows this answer.
Randy