We use Molex not JST and it is never related to channel imbalance. If a Molex connector fails you have no output on one channel, not imbalance. We don't use LEMO on the cups, either, it's a Hirose-style connector.Not the LEMO headphone cable connectors in the ear cups.
The culprit is the internal JST connector that connects to the planar driver.
Channel imbalance will be obvious during regular use as all sounds will be panned slightly to one side.
Imbalance in the AEON line was a historical issue related to the original mechanism for getting contact to the driver which could result in an intermittent or high-impedance connection, this was the source of imbalance. The problem wasn't huge but it was the biggest support issue for AEON, so the system was totally redesigned in early 2024 to use the approach we developed for Stealth, Expanse and E3, which has been extremely reliable. As a result channel imbalance for AEON 2 made after March 2024 and 100% of NOIRE X is an order of magnitude lower than older units and is no longer a material support issue.