Qwen3.8 125B (6B active) Flash-Next

User reports a decode throughput cliff on a Mac mini M4 Pro 48GB running Qwen3.8-Flash-Next 4-bit via Slotstream. Below 32,768 active tokens decode is about 11 tok/s; above it drops to 3.8-4.0 tok/s. The transition is sharp: 32,320 prompt tokens gives 9.49 tok/s, while 32,770 gives 3.84 tok/s. Setup uses a 26 GB expert pool, 65,536 max context, and MTP off. The user notes MTP on this machine is slower (about 3.7 tok/s vs 12 tok/s off) and disabled it for these tests.