The Unsloth llama.cpp guide[1] recommends building the latest llama.cpp from source, so it's possible we need to wait for LM Studio to ship an update to its bundled llama.cpp. Fairly common with new models.

1. https://unsloth.ai/docs/models/gemma-4#llama.cpp-guide

LM Studio shipped this update. Under settings make sure you update your runtimes.