When googling for "ns_param maxinput" I found the same info at sourceforge, and it also says:
> Be aware that if you expect large requests (to support file uploads, for example), you may need to specify a receive timeout. This defaults to 30 seconds. The parameter for this is named 'recvwait' within the socket driver module and is specified in seconds. <
So for uploading large mp3 files and other stuff via DSL one should also add e.g.
ns_param recvwait [expr 20 * 60]
for 20 min. timeout.