Pressure keeps dropping from loop

[Kevin Key]

I'm getting my pressure values via MQTT and the rest of my data (temperature, humidity, wind, etc.) via SDR. When the MQTT and SDR packets don't line up, the pressure get dropped and a null value gets sent to Weather Underground.

How can I stop this from happening?

[bell...@gmail.com]

Let me see if I can summarize your various posts. You are running the SDR driver and augmenting the data it captures with pressure via MQTTSubscribeService. The pressure is published frequently enough that it should be in every loop packet. You are uploading to Weather Underground using rapidfire. Because some of the packets do not have pressure data, there is nothing to upload (for more info see, https://github.com/weewx/weewx/wiki/Barometer,-pressure,-and-altimeter).
Without a log file it is hard to know why the pressure data is not being added.
You could try not using rapidfire. For a similar problem see, https://groups.google.com/g/weewx-user/c/e8jm-kZCB0E/m/bg3wn_TbAgAJ
Not sure this will work... You could run rtl_433 in a separate process (cron, service, etc.) and have it publish to MQTT. Then just run MQTTSubscribeDriver to get all of the data. Perhaps processing all of the data 'at once' to create the packet will eliminate the timing issues.
rich