When you find yourself trying to remember a show (or any works) that's on the tip of your tongue but just out of reach, come here - the collective brain of the TVTropes community can probably help. Post all the details you can remember (examples help). If you're looking for a trope, head over to Trope Finder. Have general questions about tropes? Visit Ask The Tropers!
Yes, 100%. I remember this so well, but can't for the life of me find it.
I don't remember when i watched it... i recall it being sometime around 2011 or so (my senior year of college... but i can't remember exactly).
I found this https://www.youtube.com/watch?v=Y6RuK8XGm_c
but this isn't quite right. it has a similar vibe, but i remember the exact scene you are talking about.
I took the time to recreate what i remember from memory. http://files.daveeddy.com/king-ramses.mp3
. That is an edit i've made with the original episode audio + some hardstyle kick drum sample. This is pretty much exactly what I remember. I distinctly remember hearing the phone number get dialed 4 times (Eustace only dials 4 buttons), so that's 4x the 4 note pattern. Immediately that is followed by each note being played 8x at the same speed, followed by the kick drum.
This video was so dumb but it was so memorable - I hope it hasn't been lost to time.

Does anyone remember a specific You Tube Poop of the Courage the Cowardly Dog episode “King Ramses’ Curse” where Eustace dials his phone in time with a loud hardcore techno beat? I recall the overall quality of the poop being pretty poor, and it may have been split into two parts. I watched it three years ago or less.