Ant+ connectivity issues

Hi all,

Trying to get some advice on ANT+. Currently using a TACX FLUX S trainer.

I am running Zwift on a MBP with an ANT+ within 3 feet of HRM, Cadence sensor & trainer by using an extension cable.
Zwift pairing screen is showing ANT+ connected with both power source, cadence & heart rate at start up. Everything looks good here and I start using Zwift.

About 15-20 min into the ride, avatar stops moving. “-” appears under Watts, RPM & BPM.
I stop riding on the trainer, go to pairing & check out what happens under the pairing screen.
HRM, Power source & cadence show the pairing with their previously paired equipment but with a “No signal” warning.

I normally save the ride, re-start zwift & when going into the pairing screen in the new instance of Zwift, paired sources now successfully show up without any “no signal” message. And the cycle repeats within half an hour.

On my most recent ride, I did not do that but kept persisting with trying to re-pair in the existing instance of Zwift.

The strange thing is when I go to zwiftalizer to analyze the file, it shows an absolutely strong signal. The problem occurred just after 1050pm. And I resumed riding after the signal was picked up again slightly after 11pm.
During that period between 1050-11, you can see that the signal is maxed out and consistent, better than when the ANT+ signals were actually being read prior to 1050pm. But zwift kept showing “no signal”. I cannot reconcile “no signal” showing on Zwift pairing and yet the signal showing at 100%.

Has anyone else experienced this or know how to troubleshoot this?

did something happen at this time, like did you turn on your fan or is something running in the background of the macbook that would cause the signal to drop?

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No changes in physical surroundings nor connection settings. And the drops always happen within 15-20min into the zwift session.

I would pair like you normally do, go watch TV, come back in half an hour and see if it has unpaired. If it hasn’t and you need to be riding for it to unpair then I would suggest the trainer is overheating.

Zwiftalizer has nothing to work with when there is a total loss of signal. It works by subtracting the RxFail messages in the log from the assumed perfect signal (4 messages per second per channel). But when there is a total connection failure there aren’t any RxFail messages logged so it subtracts nothing and the signal appears like it’s maxed out when in fact it’s a total failure. I thought about inverting it to only show error messages, but that wouldn’t work either because in the case of a total signal failure there still wouldn’t be any RxFail messages to plot. The only thing I can think of that would ‘fix’ this is to zero out what looks like a perfectly maxed out signal because that never happens.

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There are potential causes for wireless signal interference when using an ANT+ sensor indoors!