I cannot reproduce this behavior with several songs, but you explicitely mentioned XP as the Windows version, so there is the possiblity, that this is a bug in the legacy code. I cannot test this further, as I don't have an XP machine anymore (running 8.1 x64).

The channel manager has absolutely no influence on the module producing output or not, not even on Windows XP. Is it possible that you were playing a module that has a fade-out at the end, or sets the global volume to 0 in other ways? Many modules do that, so if you play them a second time they will stay silent, no matter if the channel manager is open or not.

Hi,
Yes, I am playing the demo sound "coda rosemario" which has got a fade out at the end ! and the second time : no sound whereas you have got ligthning under each channel and nothing lightning on the main mix... So this is a problem of module. Perhaps you should reinit a module when you play it again or put the main volume as this should to prevent this kind of problem ;)
So, no problem with channel manager as I was thinking at the beginning.
Best Regards,
Fred

Perhaps you should reinit a module when you play it again

OpenMPT used to do this but it is not what other trackers do, so modules made with other trackers are not played correctly. Yes, there are modules which exploit the fact that channel state is different when the module starts to loop.