does anyone know how to make working rocket fly sound?

i remember vaguely someone on youtube i think showcased it (but i dont remember the link) so it's possible i believe?

but the closest i ever got was the sound plays on the projectile but either updates too fast (so the sound just keep restarting) or updates too slow (plays at locations that the rocket has long left...)
- as opposed to a looping sound smoothing playing and following the rocket 

Vanilla Quake can't truly do this, produce a sound that smoothly changes location relative to the listener. Anything done in vanilla quake will have been a hack involving repeating a sound. If you were really skilful at the hack, you could create a sound clip that fades out and overlap multiple copies of it to disguise the trick a bit. But it would never be seamless, and a rocket is kind of the worst case because it moves so fast.

The only way to do this properly would be to create a modified engine that included this feature. 

Hi. I'm writing QC compatible with the original Quake engine. I'm currently trying to write a *func_pushable* which can also drop onto a lower ground when pushed off an edge. I got the pushing code working but when it drops onto lower ground, it does not detect it and continues to fall forever.

Getting gravity code to work for brushes seems to be very tricky with the original engine. Can someone tell me what I'm doing wrong?

Here's my code so far:
https://github.com/ValentineQwerty/vqmdk/blob/master/qc/entities/pushables.qc 

I have a feeling you have more problems than you realise right now. If you push the box into a wall instead of over a ledge, what happens? How about if you try and push the box up a slope? What does that tell us about SOLID_BSP?