IRQ conflict is a reasonable hypothesis: virtually all devices have an IRQ (Interrupt ReQuest) to talk with the central processor unit. When a given device (such as a printer or a sound card) calls the CPU to treat some instructions, it requests and interrupts it for a moment. When two components share the same IRQ (possibly the sound and network cards on the Who
's computer), the CPU cannot identify which device calls, causing unexpected results. For example, the early ISA sound cards use the IRQ 7 by default, just like the LPT ports. Therefore, it was impossible to listen music and print a document at the same time. Later, sound cards move to the IRQ 5 by default. I know there exist devices that don't have an allocated IRQ today (graphic cards on some computers), and the IRQ management have changed since Windows 2000. From DOS to Windows 9x era, IRQ conflict was a recurrent issue. Alongside Windows XP, virtually all systems - even monoprocessor ones - support APIC (with much more IRQs available than PIC: 200+ instead of sixteen).
Big Monstro, I don't think I enabled the IRQ for the ens137x cards.
Do you mean the sound card (with your driver loaded) simply cannot request the CPU? Only the CPU can talk to the sound card and not the opposite?
Windows 3.1 requires the protected mode for memory allocation, so, why Who
wouldn't able to use both sound and network at the same time?