Turn down the suddenly pounding volume of the rhetoric between Vietnam and China over disputes in the South China Sea, and a softer backbeat can be heard.
For all the tit-for-tat exchanges of recent weeks, there have still been signs of co-operation - and not all of which were apparent a year ago. There have been joint patrols in the Tonkin Gulf, a first round of talks on less sensitive issues such as environmental protection and search and rescue, as well as the opening of negotiations to demarcate the mouth of the Tonkin Gulf. The progress has been fuelled by intense diplomacy to rein in tensions and not let them poison the broader fraternal, if suspicious, relationship - an effort symbolised by an 'agreement on fundamental principles' signed by President Hu Jintao and Vietnamese Communist Party chief Nguyen Phu Trong last October.
The opening of Tonkin Gulf talks in late May, including possible joint development, is significant. Since normalising relations in 1991, Beijing and Hanoi have quietly worked to solve the dispute over their war-torn 1,400-kilometre land border and agreed to carve up the Tonkin Gulf on equidistant lines.
The question now is whether that hard-won progress is about to collapse, or whether it can somehow continue, despite tensions. Turn back up the volume, and that backbeat is drowned out.
Certainly, it has been a bruising few weeks. Hanoi's moves to codify its claims to the Paracel and the Spratly archipelagoes into a national maritime law, as well as regular jet-fighter patrols, have been met with strong countermoves from Beijing. China has created a new administrative 'city' for both island groups and is taking steps to fortify facilities and build up military forces to divisional strength. Most significantly of all, state oil giant China National Offshore Oil Corp has announced that it will accept bids for exploration blocks near Vietnam, some of which have already been let out by Hanoi to international firms.
In response, street protests flared in both Hanoi and Ho Chi Minh City at the weekend - a vexing problem for Hanoi's party chiefs, and moves that will not be appreciated in Beijing.