Alchemy Transmute spec not functioning correctly with Transmute: Arcanite

Transmute spec not functioning correctly with Transmute: Arcanite.

steps to reproduce: transmute a large amount of arcanite on a character with transmute specialization.
expected results: some mixture of procs of 2x, 3x, etc, at a reasonable rate, generally estimated between 10% and 20%.
actual results: only one transmute mastery proc, 4x, over the course of hundreds of transmutes.

obviously with hundreds of transmutes we’re well past the point of a bad streak of luck. seems broken, possibly only allowing the transmute spec proc when it rolls the rarer outcomes?