Hello Zwifters!
Since last update 1.0.65416 (2021/03/24) Stryd is no longer giving consistant speed values to Zwift.
Paired via Bluetooth and Companion App speed was off from normal by about 10% and rather fluctuating. (activity number 777404099446336016)
I gave it another try with Stryd paired directly to Laptop (WIN7) via ANT+. This resulted in multiple dropouts where my avatar came to a complete standstill.
(activity number 778038433735931584)
Zwiftalizer reports AVG RXFAILS 6.22% for the Stryd channel on this one.
Is there something broken in Zwift since the update or is my Stryd coincidentally broken on the same day? … and yes, battery of Stryd is charged 
This is completely new, i´ve never had any issues with Stryd and Zwift before.
Edit: the ANT+ Dongle is located less than 1 m left from treadmill/left foot with Stryd, … the Garmin watch (backup) recorded not a single dropout during the session.
Edit 2:
i´ve found several warnings in the Launcher_log.txt from the session where this update was applied, i´ll paste the suspect lines here. Any ideas?
[10:33:11 2021-03-24] Patcher: “APR2007_xinput_x64.cab” file verify failed – Date-time stamp differs. Passed=2018-04-18 03:56:54.958, Actual=14:51:30 2015-08-27
[10:33:11 2021-03-24]
Patcher: ERROR: “APR2007_xinput_x64.cab” failed the file integrity test (modified=2018-04-18 03:56:54.958, length=96817)!
[10:33:11 2021-03-24] Patcher: “Feb2010_X3DAudio_x64.cab” file verify failed – Date-time stamp differs. Passed=2018-04-18 04:17:45.521, Actual=14:51:30 2015-08-27
[10:33:11 2021-03-24]
Patcher: ERROR: “Feb2010_X3DAudio_x64.cab” failed the file integrity test (modified=2018-04-18 04:17:45.521, length=54678)!
[10:33:11 2021-03-24] Patcher: “Jun2010_XAudio_x64.cab” file verify failed – Date-time stamp differs. Passed=2018-04-18 04:17:46.663, Actual=14:51:30 2015-08-27
[10:33:11 2021-03-24]
Patcher: ERROR: “Jun2010_XAudio_x64.cab” failed the file integrity test (modified=2018-04-18 04:17:46.663, length=277338)!
[10:33:22 2021-03-24] Patcher: “data\configs\medium.txt” file verify failed – Date-time stamp differs. Passed=2015-09-06 23:30:45.139, Actual=17:27:38 2018-10-30
[10:33:22 2021-03-24]
Patcher: ERROR: “data\configs\medium.txt” failed the file integrity test (modified=2015-09-06 23:30:45.139, length=170)!
[10:34:49 2021-03-24] Launcher: Starting Zwift App.