PowerFlarm BRICK range issues - are we alone????

Three members at my club (self included) have installed PowerFlarm bricks recently. We carefully read and have complied with the antenna separation requirements in the manual. As is stands currently, the maximum xperienced communication range (Flarm to Flarm) is about 2.2 miles and it frequently drops out around 1.3-1.5 miles. Regarding PCAS operation, the only alert I have received using the PowerFlarm Brick has been the towplane at a distance of about 1000-1500 feet lateraly, same altitude. At the same time my Zaon PCAS alerted to the same towplane at a range of 2+ miles and 1000 feet below.

The three gliders are a Ventus 1, Discus 2, and a PIK. All three seem to be experiencing the same issues with very poor range. Emails to FLARM have seemed to fall on deaf ears. We're curious if we're the only ones or if others are also seeing the same issues with BRICKS. We've heard plenty from portable users who are reporting 6+ miles Flarm to Flarm and PCAS alerts approaching 5 miles. If changes to the installation will fix this, great! We just need to know what to change. The US dealer has seen pics of our installation and says the antenna installations look good. They are all on the top of the glare shields so should be excellent visibility. We'd like this to work, but if there is no option to improve the performance then sending the stuff back is certainly on the table. More testing this weekend, but at the moment it's not looking good.