This article describes a rare issue that can occur with UAFX Starlight Echo Station pedals and version 1.0.0 firmware.
Symptom: When the Precision effect is selected and the FEEDBACK knob is set to maximum, the delayed signal can degrade and may eventually not be heard.
Solution: Reduce the FEEDBACK knob below its maximum value. This issue will be fixed in a future UAFX firmware update.
Background: Normally, the Precision effect can be set for maximum feedback and the delays will cleanly repeat indefinitely. However, if Starlight receives an audio signal from another device that contains a high DC offset while Precision feedback is set to maximum, the delayed signal can degrade until it eventually drops out altogether.
For more information about DC offset, see this article from Sound On Sound.