Looping sound > start then stop

[ajay]

[Lardarse]

[Spike]

and from a QC perspective:
a sound is replaced if you play another sound on the same entity+channel (except not channel 0).
this is true whether the old sound was looping or not.
so you can stop a sound by playing a null sound.
note that this is similar to the sounds made by moving trains (except that the replacement sound is not silent in that case).

with qw engines, be careful about phs (replacement sound should have no attenuation)...

[ajay]

[Lardarse]