Placing a silent sequence on my main timeline brings in unwanted audio track

I'm pretty new to Premiere Pro. I've created a new Sequence containing a short animation about three seconds long with no audio. I plan to use it in multiple projects. Over in my main video timeline, I dropped the animation sequence in, and it overwrote my background music track with silence for the duration of the animation. Where did that silent audio track come from? How do I tell Premiere not to bother trying to import audio from it? Do I need to open it in the Source Monitor first and manually drag it in as video only? I don't think that would even work, as double-clicking the Sequence just opens it in the timeline instead of the Source Monitor. Should I have created the animation as a Subsequence instead? That doesn't seem to make any difference.