The Bottles' Bonus Note Glitch is a glitch exclusive to the Xbox Live Arcade Version of the first Banjo-Kazooie wherein the Bottles' Bonus game can cause some of the games Musical Notes to be impossible to collect. The game has since been patched to remove the glitch.
How to Perform the Glitch
To make this glitch take effect, one simply had to play through and beat the Bottles' Bonus games in Banjo's house (by entering Banjo's house and hitting Y to look at the picture of Bottles) but it must have been done before the player entered Mad Monster Mansion for the first time. If done correctly, 4 notes from Mad Monster Mansion, 4 Notes from Rusty Bucket Bay and 4 Notes from Click Clock Wood will have disappeared and become impossible to collect, thus making it impossible to collect all 900 notes in the game.
The Cause of the Glitch
The reason this glitch occurs comes from a new feature in the Xbox Live Arcade Version of the game. In the original Banjo-Kazooie, dying or leaving a level and coming back would result in the Musical Notes being reset as though the player had never collected them. The Notes collected in any given level are recorded as collected via a "high-score" system with 100 being the highest one can obtain. For the game's sequel, Banjo-Tooie this was changed so that when the Musical Notes are collected, they remain collected even when the level is re-entered later. When Banjo-Kazooie was ported to the Xbox Live Arcade, the developers made this feature standard for both games, meaning now collected notes remain collected no matter what. When adding this feature however, the developers didn't take into account the Bottles' Bonus mini-games. The puzzles in the Bottles' Bonus feature video of Banjo playing through portions of levels, including Mad Monster Mansion, Rusty Bucket Bay and Click Clock Wood. These videos aren't pre-recorded however, and are generated as live computer-controlled demos using the game's engine. Because of this, the game considers the computer Banjo in the videos as the player, and thus when he collects the Notes in the videos, the game believes they have already been collected and removes them from the game. Worse still, the computer's collected Notes do not count towards the player's actual total. Meaning, essentially, they are gone.
Avoiding and Fixing the Glitch
Avoiding the glitch was easy, it simply involved not playing Bottles' Bonus at all until after getting all of the notes in the affected levels. This is no longer an issue however, as the developers have released a patch that fixes the glitch. If you aren't sure whether or not your game is still faulty, simply log onto Xbox Live when next you start the game and it should check for and automatically patch the game if yours is out of date. While the patch does fix the problem for new sessions of the game, if your save file was created before the glitch and/or you have already caused the glitch, the patch will not fix anything for that save file. Luckily, the glitch still allows you to collect enough notes to get everything else in the game including opening the final Note Doors just before the end, but you will need to create a new save file in order to get all 900 Notes.