Headphone and Chest HRM keep disconnecting

I get the same problem. I've got a Stryd footpod, Wahoo Tickr HRM and Trekz headphones. I very often get a couple of dropouts per run.

I want to use the Stryd for pace/distance as it should be more accurate than GPS but if it drops out for a period of time it completly throws the pace and distance off.

Very frustrating as everything else about this watch is great.

Sometimes I have an issue, that the chest strap HRM RUN2 is disconnected for few seconds. But I am not too concerned about this while it works usually properly. Havent tried to use any BT functionality together with chest strap. I only know, that some time ago, the activity was not synced with the GC if the chest strap was still connectred (e.g. using heart rate widget).

Same here.

I get the same problem.
I've got a Stryd footpod, Polar H10 HR Belt and Pioneer SE-CL5B headphones. Disconnect on every run (Headphone and Stryd). It never disconnet when using only Stryd+Polar Belt.

I give it up using music during race. I still use music during training but it's frustrating...

I hope a new firmware sometimes soon. I appreciate the watch, except the music feature wich didn't work great since the beginning. I choose this watch for music....

Well, if I had to choose now, I would prefer buying a separate and very small MP3 player with bluetooth, like for example a SANDISK Clip Sport Plus as the music feature appears to ruin most of my runs since 1 year.

Are people still having issues with this or has anybody found cause/solution? I have footpod, headphones and hrm run all disconnect at the same time between 20-35mins into every run ???? very annoying!

A complete factory reset (including the delete of music/activity) has improved stability for me. I didn't reinstall Spotify yet, just transfered 3 albums via garmin express and did make as little changes to settings as possible.
As a result, out of 4 runs with HRM4-Run and BT-Headphones (no smartphone connected during run), there was one short drop in heartrate recording, 3 runs (1 hour each) had no dropouts at all. Before the reset, I had typically one dropout after ~35 minutes, when i lost heartrate and BT connection at the same time, most of the times both re-connecting after a few seconds, but twice I had to manually initiate the reconnection (which is most annoying during a run).

Thanks I'll give that a try, mine currently disconnects for about 10mins when it does go so need to try something!

Saw this as well a few times at a marathon last weekend, my 645 (non-music) dropped the connection to both a Garmin HRM & a Stryd footpod. Common problem it would appear. Both at the same time so would suggest the problem is on the watch.

Are people still getting this problem? 

I am getting fed up with the dropouts. I contacted Garmin back in January and they said they were fixing it. I asked if firmware 5.2 included the fix and was told yes.

A 4.6 mile run yesterday and 4 dropouts.

Garmin are washing their hands of this now, saying nothing they can do as the headphones are not supported. Have tried 2 separate headphones and their very own Garmin heart rate strap has a drop out at the same time.

There was no issue on launch but introduced somewhere along the line.

Have you tried to run HRM and bluetooth headphones during activities that do not use GPS, such as cardio or strength exercises?

I have and guess what? There were no problems with the simultaneous operation of HRM and headphones. But as soon as I started the activity using GPS (e.g. running) the drpout of connection with the headphones and HRM immediately appeared. Conclusion: the problem is not related to the model of headphones nor firmware version. It's related to GPS hardware in some models of 645M.

I reported and described the problem at my local Garmin distributor. They did not even try to repair anything. They simply replaced my watch with a new one. In my new 645M there are no problems that you describe here. So I  guess Garmin had to change something in HW in newly produced watches. Replacement made under the warranty. This is what I suggest you should do: stop seeking and replaced your watch. This is the best you can do.

Regards