Data loss (skipping) using Flume with Kafka source and HDFS sink - hadoop

Question

I am experiencing data loss (skipping chunks of time in data) when I am pulling data off a kafka topic as a source and putting it into an HDFS file (DataStream) as a sink. The pattern seems to be in 10, 20 or 30 minute blocks of data skipping. I have verified that the skipped data is in the topic .log file that is being generated by Kafka. (The original data is coming from a syslog, going through a different flume agent and being put into the Kafka topic - the data loss isn't happening there).
I find it interesting and unusual that the blocks of skipped data are always 10, 20 or 30 mins and happen at least once an hour in my data.
Here is a copy of my configuration file:
a1.sources = kafka-source
a1.channels = memory-channel
a1.sinks = hdfs-sink
a1.sources.kafka-source.type = org.apache.flume.source.kafka.KafkaSource
a1.sources.kafka-source.zookeeperConnect = 10.xx.x.xx:xxxx
a1.sources.kafka-source.topic = firewall
a1.sources.kafka-source.groupId = flume
a1.sources.kafka-source.channels = memory-channel
a1.channels.memory-channel.type = memory
a1.channels.memory-channel.capacity = 100000
a1.channels.memory-channel.transactionCapacity = 1000
a1.sinks.hdfs-sink.type = hdfs
a1.sinks.hdfs-sink.hdfs.fileType = DataStream
a1.sinks.hdfs-sink.hdfs.path = /topics/%{topic}/%m-%d-%Y
a1.sinks.hdfs-sink.hdfs.filePrefix = firewall1
a1.sinks.hdfs-sink.hdfs.fileSuffix = .log
a1.sinks.hdfs-sink.hdfs.rollInterval = 86400
a1.sinks.hdfs-sink.hdfs.rollSize = 0
a1.sinks.hdfs-sink.hdfs.rollCount = 0
a1.sinks.hdfs-sink.hdfs.maxOpenFiles = 1
a1.sinks.hdfs-sink.channel = memory-channel
Any insight would be helpful. I have been searching online for answers for awhile.
Thanks.