When several noteblocks are placed in a row and activated by a fast repeater clock, a few noteblocks on the further side of the row do not play any sound when standing towards one end of the row. At a certain distance, further noteblocks randomly play or do not play sound when activated. When the repeater clock is slowed, this does not occur.

Expected result:
Any limit that might exist on how many noteblock sounds can be played at once is applied consistently.

Actual result:
Sometimes, but not always, several noteblocks of a larger group will not play sound when activated together.

How to reproduce:
1. Place a row of nine noteblocks with varying pitches and/or instruments to distinguish them. Remember what the noteblocks on each end sound like.
2. Place a row of nine solid blocks next to the noteblocks with redstone dust on top.
3. Place two repeaters on one tick next to the redstone dust, one facing towards the redstone and one facing away. Complete the redstone clock with two pieces of redstone.
4. Activate the clock with a one-tick pulse from a lever or observer.
5. Listen to the noteblocks from various positions.
6. Deactivate the clock, set each repeater to two ticks, and reactivate the clock. Listen to the noteblocks again.

While this bug does not damage gameplay significantly, it may make it harder for me and other players using noteblocks to make noteblock songs with both fast tempos and harmony.

The audio was recorded while standing still in the pictured setup. The high-pitched piano is the noteblock to the far right.