Increasing the multiplier past a certain point causes sounds on a Quantization Boundary to struggle to play at the correct time. The repro above uses 1/32, but this also repros with other values.
See video [Link Removed]
This does not occur in 4.27 and is a regression.
1) Launch AudioQA
2) Open the AQ_Quartz map
3) Select the SimpleTestClock_BPM asset
4) In the Details panel, change In Quantization to 1/32
6) Enter the Simple Test Clock - BPM test box
7) While the click is playing, change the Multiplier to 2.0, then 4.0, then 8.0, then 16.0, then 32.0
Increasing the multiplier increases the boundary that the sounds are scheduled on. 2.0 will be a 16th note boundary, 4.0 an eight note, 8.0 a quarter node, etc.
As the multiplier goes up, the boundary stops changing correctly
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-152190 in the post.