ansible bigip_pool_member intermittently not adding member to pool

We have an ansible script that we are using to move nodes in and out of pools for testing that intermittently refuses to add the pool member thinking we are trying to add it to the root folder. The issue is that the failures are now happening almost every time, despite no changes to the script and no recent changes to our F5. Verbose mode shows it has the correct partition, but somehow that partition info is not being read or taken in properly. Thanks in advance for any help. ansible version 1.9.1 (and stuck on this version for a while)

Here's what we see when running the playbook:

TASK: [enable new nodes on external checkout pool] ****************************
<127.0.0.1> REMOTE_MODULE bigip_pool_member server=10.10.10.10 user=myuser password=VALUE_HIDDEN state=present pool=EXTERNAL_CHECKOUT_POOL **partition=WEB-GENERAL-CORE** host=MYHOST14 port=2180
<127.0.0.1> EXEC ['/bin/bash', '-c', 'mkdir -p $HOME/.ansible/tmp/ansible-tmp-1457566442.5-241342532701996 && chmod a+rx $HOME/.ansible/tmp/ansible-tmp-1457566442.5-241342532701996 && echo $HOME/.ansible/tmp/ansible-tmp-1457566442.5-241342532701996']
<127.0.0.1> PUT /tmp/tmp59N5mT TO /home/myuser/.ansible/tmp/ansible-tmp-1457566442.5-241342532701996/bigip_pool_member
<127.0.0.1> EXEC ['/bin/bash', '-c', u'LANG=C LC_CTYPE=C /usr/bin/python /home/myuser/.ansible/tmp/ansible-tmp-1457566442.5-241342532701996/bigip_pool_member; rm -rf /home/myuser/.ansible/tmp/ansible-tmp-1457566442.5-241342532701996/ >/dev/null 2>&1']
failed: [localhost -> 127.0.0.1] => (item=MYHOST14) => {"failed": true, "item": "MYHOST14"}
msg: received exception: Server raised fault: 'Exception caught in LocalLB::urn:iControl:LocalLB/Pool::add_member_v2()
Exception: Common::OperationFailed
        primary_error_code   : 17241203 (0x01071473)
        secondary_error_code : 0
        error_string         : 01071473:3: Create, modify, and delete commands are not valid for (by class: pool_member) while in the root folder.'

FATAL: all hosts have already failed -- aborting