This page contains spoilers about the Heartbound ARG. If you want to solve the puzzle yourself, avoid reading this article.
As always, look to the source. We get a digit string and a character string. No hints on either.
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<div class="12410162315372">
<!-- DHPHBAAJKEPTBGACUKKTKGRFULKDKAGFDLTDSAGJ -->
</div>
12410162315372[]
First surprise, "12410162315372", despite being in the usual "hint" position, is actually the ciphertext. "DHPHBAAJKEPTBGACUKKTKGRFULKDKAGFDLTDSAGJ" is, conversely, the key.
The first thing to do, is correctly space out the ciphertext:
12 4 10 16 23 15 37 2
Once you've done that, and noticed that they're all numbers less than 40 (which, circularly, is why they need to be spaced out like that), check out the letters in the "key" at each position:
12 T 4 H 10 E 16 C 23 R 15 A 37 S 2 H
Add "THECRASH" to your URL, and you'll get to The Sound Of Silence.