Write the signal path before connecting
List the computer or digital source, DAC, headphone or receiving amplifier, and speakers if present. A DAC’s line output is not a power output for passive speakers. Pick one supported input and one listening output for the first test rather than connecting every socket.
Check power and cable roles
Use the power supply specified for the exact device and confirm the supplied package with the seller. A USB-C socket may carry data while a separate connector supplies power. For the K11 R2R, use FiiO’s exact-model documentation instead of instructions for the ordinary K11 or another desktop unit.
Establish safe volume control
Pause playback, lower the listening level and choose the documented output mode. A fixed line output requires suitable downstream volume control; a variable pre-output has a different role. Confirm which knob changes the level before playing a quiet familiar passage. Do not switch modes during loud playback.
Test the computer and app separately
Choose the intended output in the operating system and check the player’s own device setting. If music works but calls do not, inspect the meeting application and microphone selection. A music DAC and passive headphones do not automatically provide a microphone input.
If a Windows player closes instead of producing sound
Checked on 20 October 2026: Microsoft says the Windows built-in AC-3 app-crash issue was repaired by the 13 October KB5127648 update or later updates. This is a manufacturer repair claim, not a HiFiNaija or SoundPath Lab retest or independent owner confirmation. Record the exact Windows branch/build, app and triggering file, then compare the same playback path after an applicable official update. A crash alone does not prove a K11 R2R fault, and this repair does not close the separate USB Audio Class 1 issue. Read the linked SPL record for scope and the still-unverified outcome.
Check everyday recovery
Test a normal sleep/wake cycle, reconnection and the return to your usual input. Record whether speakers mute when you choose headphones instead of assuming automatic behaviour. Keep a short note beside a shared desk explaining input, output and the everyday volume control.
Use research to answer the next question
SoundPath Lab’s audio/control planning example is useful for separating signal delivery from power automation, but is not a test of this desktop setup. Once the basic path works, decide whether any missing function remains. Do not use mode names or bigger numbers as evidence of an audible improvement.
Research & owner resources
Read the original evidence and its date. Manufacturer documentation, editorial analysis and owner reports are different kinds of evidence. These references do not establish Nigerian stock, warranty or local testing.