2209 speed and cadence work flawlessly commuting to work in morning. However, riding home at 6pm the speed & cadence only works 25% of the time. Could it be the NiteRider Lumina 650 headlight mounted next to the 2209 main unit near stem? I do use different light settings during the ride and possibly the 25% is when the light is on the low setting (hard to correlate because it is dark). The headlight is off in the morning. If it is the light, any shielding possible? Not sure I can separate the 2209 and light by distance.

Thought it might be because the speed and cadence sensors sat outside in the cold all day (main unit taken off the bike during day) but now suspecting the light after reading a post or two. No low battery warning but replaced the speed sensor battery with no different results.

i have heard that a few other sigma owners also. The ones that have problems seem to have their light very close ( all most touching ) and the light in strobe mode. I have a 1609 on my rode bike (havent fully tested it yet) and have no problems so far.

Yes, they are almost touching. 2209 on the stem and the light just to the right. Maybe I'll try moving the 2209 to the left side of the bar or try wrapping the light in tin-foil.

Hope that helps. Maybe try to see what modes cause that to happen then dont u that mode if u can.

Well, wrapping the light almost entirely in tin-foil has partially solved the problem. The speed sensor now works but the cadence sensor still doesn't work. Since I can't see the cadence sensor in the dark, it isn't that big of a deal. Glad the speed sensor is working to record my miles.