Per-second countdowns have delay between some counts

[JDLH]

I use the Interval Timer for 6 intervals with 2 minutes exercise, 2 minutes rest. During the audio countdown of 10 seconds to the end of exercise, the app speaks the numbers "10", "9", etc. at roughly 1-second intervals. However, there is a delay before some of the numbers, usually before "8" and "4".

To reproduce:

• Turn on audio for countdowns to the end of an exercise or rest period
• Set up an exercise pattern of 2 minutes exercise and 2 minutes rest, with 6 repetittions
• Start the exercise
• At the end of the exercise interval, listen to the audio countdown of seconds until the end of the interval. Note the time between each number.
• Similarly, at the end of the rest interval, listen to the audio countdown of seconds until the end of the rest interval. Note the time between each number.

Observed behaviour:

• Usually, the time between "9" and "8" is longer than the interval between "10" and "9" or between "8" and "7".
• Usually, the time between "5" and "4" is longer than the interval between "6" and "5" or between "4" and "3".
• Sometimes, the delay occurs between other pairs of numbers. The delay is not consistent for every interval countdown in a single exercise program.
• Times between other pairs of numbers is approximately equal.
• I have not measured the time intervals between spoken numbers to see if they exactly equal 1 second.

Expected behaviour:

• Equal time interval between each spoken number in a countdown to end of interval. No pauses or hesitation.
• This time interval is 1.0 seconds +/- 0.1 seconds.

Test environment:

• Privacy Friendly Interval Timer app v 1.2
• Google Nexus 6P phone
• Android 8.1.0