Although I think it probably would have made sense for these to be in a separate thread, as you have done, I’ve actually been pointing out these glitches in the “Big news - exciting times” thread itself.
Glitches like these are at least part of the reason why the course is still described as being in Beta; and pointing them out is genuinely helpful to the process of fixing them and getting it beyond that stage. I think the team are possibly already aware of all three of these specific issues, which means that fixes for some or all of them are already on the way - but please do let them know of any more that come up. Ideally, if you can give really specific information as to which word/sound file has gone wrong (eg in the white noise cases), that will probably be even better.