Data display periodically freezes

[produceconsumerobot]

Potentially 2 separate or related issues:

1. Data temporarily freezes at periodic intervals. Smells like a garbage collection issue. It's not a big deal in and of itself, but it seems to indicate that our oscilloscope may not be handling memory management super well. May be related to 2nd issue and app crashing issue App sometimes crashes when switching data streams #12

2. Occasionally the data will get into a permanently frozen state, while the app UI continues working. On one occasion after hitting record the data display froze, but when I changed data types the data would refresh one time and then freeze again.