it happens when launching the game however returning to the menu from a route does not trigger it
Best I can think of is that maybe the logo is trying to display at the landscape layout's size, but is cut off by the borders of the portrait layout's size. If that's the case, swapping layouts a few times might fix it. However, that can be a bit wonky sometimes (since sometimes it crashes instead of restarting a few times), so I'm not sure I recommend that if everything else seems to work. I can look into it, but I'd probably need different hardware to test it...
For the music, my main recommendation for the moment would be to lower the volume in the game settings. (I usually have it at ~60% for my testing.) I used to have code in some of my games that would default the music volume to something other than 100%, but it didn't always work because it would have to be a fresh install, thus its removal. I can potentially look into putting it back in, but it would still require a clean install to do anything in its current form. (Otherwise, the player's setting would get overridden.)
(If the problem continues even with the game volume lowered, you may have to also lower the volume on your PC/phone. In my experience, headphone volumes over 40% can become deafening really quick, and my phone requires a toggle to allow past 70%.)