Same issue as all of the above, new calls are always at 100% and if we leave a call and then go back to it the volume also goes back to 100%.
But also noticed a new hiccup, when we join the Teams call we used to be able to drag the Teams app volume down to 0 if we needed to grab an IRL web phone call using the same headset (wired, not wireless or Bluetooth, and using the 3.5mm jack, not USB). As of this week when myself or my coworkers drag the volume down to 0 with the system volume at 100 we still hear teams audio as if it was at level 15-20 previously. The only person NOT having this issue is the one using her speakers for the Teams call rather than a headset since her Bluetooth headset will only accept one input, either Webcall or Teams, without muting her. The one bonus to her dog chewing the wired headset's cable.