OK, next step - alsamixer.
Leave all the lines in /etc/moprobe.conf. Even if they don't help, they won't hurt.
axel wrote:the following line was defined by by ALSA:
alias sound-slot-0 snd-ens1371
Yes, that's for ALSA-OSS compatibility.
It's technically ugly, and I have lobbied in the past to have the ALSA-OSS modules removed. Sadly, Puppy's tray mixer (absvolume) seems to require the ALSA-OSS modules ... a good reason to replace it with a proper ALSA tray mixer ... but I digress.
Open rxvt and expand it fullscreen, then run "alsamixer".
Make sure that your Master channel and PCM channel are raised, and at the bottom they indicate "00" - which means they are not muted. When muted they will indicate "MM".
There are two particular channels for your sound chip which are known to mess up audio output - "Headphone Jack Sense" and "Line Jack Sense" - so mute them. This might fix the problem, but it not, go ahead and mute all other channels (or decrease the level). The only important channels are Master, PCM, and Wave.