[arm-allstar] problem with telemetry via localplay or playback when node is keyed

[Patrick Perdue]

I just noticed an issue with Asterisk 1.4.23-pre.hamvoip-V1.6.2-10 
app_rpt-0.327-06/01/2020 running on a repeater.

There is a file scheduled to play at a specific time through cron. 
holdofftelem=1. Thus, if there is traffic, the telemetry should be held 
until the node is no longer keyed.

What actually happens is this.

The repeater is keyed by someone from the RF side. The event is 
triggered while a transmission is happening. All audio stops passing 
between the repeater and VoIP until the end of the transmission, where 
upon the file, which was held in the queue, is played. I can reproduce 
this on my local nodes as well, simply by executing rpt playback <node> 
<file> while transmitting toward my node, and monitoring from another 
local node. This is also the case when using the included saytime 
script. In both cases, the file being played back is either sln or ULAW.