Brian,

Snom think that this flashing on hold is incorrect - I had this on my snom forum post:

No! I've never seen such behaviour - Neither the LED is supposed to 
blink when the monitored party is on hold, nor it should be possible to 
steal the call by hitting the function key. That indeed is extremely 
confusing and is definitely not intended. 

I don't have much (if at all) experience with Freeswitch but from what I
 understand, extension monitoring is being configured through dial plans
 (and?/) or the mod_snom module.

I guess something is not configured properly which results in the problem you are encountering.

It should not make any difference whether the monitored extension is set
 on hold or not. Can you post a SIP trace which shows such a scenario?

I replied with:

Extension monitoring is being done with bog-standard subscriptions, not with mod_snom or anything extra in the dialplan.

The Polycoms flash the button while a monitored line is held, but you can't pick it up.

I will try to get a trace from the phone, however someone re-used my 
test FS box for a windows desktop while I was away, so I have to build a
 new one.

Any more ideas as to why this is happening?

Cheers

Alex

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