Faint tick tick tick sound, most noticeable at slower speeds.
Looked for it for the longest time myself.
Took the bike in to three bike shops to help diagnose. Noise persisted.
Removed the tire, tube, rim tape to true the wheel after some time living with the noise.
Found metal shavings from the drilling of the aluminum rim for spoke holes. Origin8 Speed V deeper wheel set that wasn't properly deburred/polished after drilling. Shavings were held in place by the spokes and rim strip. Hit the inside of rim with sand paper, shook out, wiped down.
Problem solved.