matze79 wrote:What does sound like phonespeaker ? everything or just Adlib/OPL Emulation ?
I should have phrased this better. Everything coming from the output has a very limited frequency range, audio, MIDI, and CD. I have not yet done a frequency analysis on the output but likely will do that at some point.
As an experiment I installed a discrete ES1370 PCI card and had no issues with frequency output. However, since the onboard audio cannot be disabled as far it did cause some redundancies in device manager.
I do wonder if the onboard PCI has a deliberately limited frequency range or if it requires a different/specific driver for the onboard variant.