Best firmware to avoid sensor drop outs?

If you search further back in the 530 & other forums you will find the sensor dropouts are a constant  recurring complaint which waxes and wanes , increasing with some software releases and declines (when users give up?). It is a real problem, I have it with the connection to the resistance unit of my smart trainer and I to have gone back to 7,10 where I have not seen it. There are a lot of dropout postings around version 3 and 4 so can't really say any specific version is perfect but at that time Garmin at least said they were investigating but nothing ever reported as being done (unless included in the catch-all "improvement" in every SW release )

• "Improved general device stability"?

As I said it is a real problem for those who get it, evidenced by FIT files etc but Garmin gives the impression they don't believe it exists. Worrying that there are already sensor dropout reports in the 1040 forum**. It may be that we operate in a very noisy radio environment but that is a given and not an excuse.

PS **in the 1040 torum  a number of users are reporting sensor dropouts and suggesting these go away when they remove specific or all CIQ apps / fields so there is clearly some conditions that cause some functions / processes to affect sensor connection processes, the combinations are probably infinite ?

I've tested:

7.10

8.xx

9.30 and 9.40

with 3 different powermeters: 4iiii and Inpeak (left crankarm sensors) and Garmin Vector 3 dual pedals.

All software versions with "clear" system, so no additional 3rd party fields nor CIQ apps. I even don't pair other sensors and phone.

In all softwares and for all powermeters I have constant dropouts. FIT files are so coruppeted that any training analysis makes no sense using them. What's more interesting: all 3 powermeters work 100% perfectly with FR945.

This year I switched to 9.40 and problems started. I managed to revert to 9.1 (it's inside with the beta version ) https://www8.garmin.com/support/download_details.jsp?id=14953

I only have 2 Bontrager lights and HR strap (decathlon) all of them are ANT+.

With 9.1 the started to work properly.

Is there some place to get other versions than 9.10 and the latest 9.40? I cant find any on the internet.

The last version that was posted on the forum (rather than via Garmin connect) was 7.10 and is here

https://forums.garmin.com/sports-fitness/cycling/f/edge-530/253672/new-edge-530-version-7-10-now-available

Public Beta announcements (search "New Edge 530 Public Beta" ) include the previous production version but these downloads are usually removed after the beta

PS The other trick (but only if you did the software updates via Garmin Connect/Express on a Windows machine is to look in the directory

C:\ProgramData\Garmin\CoreService\Downloads\PrimaryFirmware

where you will find files from each update are cached. Follow the path down for the specific version you want and about 10 directories down you will find the version GUPDATE.GCD file

I reverted to 9.1, like patryk already posted here, and the dropouts are gone, at least for.me...

my experience with multiple ANT+ sensor brands is that the version is not the issue... it is always the battery, as this level drops a bit the whole system gets instable or random connect/disconnect.

I'll try to replace the battery in HR monitor but the other problem is with lamps that have rechargeable batteries. I keep them charged all the time 

have litte with the ANT+ lamps...i had the same problems at that time, as the voltage drops... the connection gets instable...

voltage drops sooner with rechargeable compared to non-rechargeable cells such as CR3032 for heartrate sensor