Events are often perceived in multiple modalities. The co-occurring proximal visual and auditory stimuli events are mostly also causally linked to the distal event. This makes it difficult to evaluate whether learned correlation or perceived causation guides binding in multisensory perception. Piano tones are an interesting exception: Piano tones are associated with seeing key strokes but are directly caused by hammers that hit strings hidden from observation. We examined the influence of seeing the hammer or the key stroke on auditory temporal order judgments (TOJ). Participants judged the temporal order of a dog bark and a piano tone, while seeing the piano stroke shifted temporally relative to its audio signal. Visual lead increased "piano-first" responses in auditory TOJ, but more so if only the associated key stroke than if the sound-producing hammer was visible, though both were equally visually salient. This provides evidence for a learning account of audiovisual perception.