Same problem for me! Freezes 2-3 times during the first couple of minutes (race and workout mode, watch mode shows no issues). After the first 3-7 minutes, no further issues arise.
Netstat shows lots and lots of open connections to an AWS instances. Is that expected behaviour?
I am using the Tacx vortex Smart with an USB Ant+ dongle and a Garmin heart-rate monitor.
Macbook Pro Retina Mid 2012 15 inch,
8GB Ram 1600 MHz DDR3,
2,3Ghz Intel Core i7,
Nvidia Geforce GT 650M 1024 MB,
Would be really fine to sort out theses issues, as racing is quite impossible this way.