When an ADDBA Response is received, the recipient may be a "QoS blocked destination" and hence any MPDU to retransmit would not be returned by PeekNextMpdu. Use PeekByTidAndAddress instead.
The fix of commit 561ed7cf was affected by some subsequent changes. This one should be the real fix.
Fixes #417 (closed)
Edited by Stefano Avallone