TBS6905 interference problem

[malakudi]

We have installed six (6) TBS6905 on a Supermicro X9DRH-7TF . This has 7 pci-e 3.0 slots and we have installed 3+3 cards, seperated by one slot in the middle. It seems that nearby tuners produce interference to each other. For example, one tuner on one card has 14.5 dB SNR but when a nearby tuner on a different card is tuned, the SNR goes down to 10 dB. All tuners are connected to multiswitch. We have also experienced the same phenomenon in tuners of the same card. For example, tuner 4 (/dev/dvb/adapter3) has 15 dB SNR but when tuner 1 (/dev/dvb/adapter0) is tuned also, the SNR or 4 drops to 11 dB.
This does not happen on TBS6985 on completely same setup. It only happens on TBS6905. Do you have a clue why? In my opinion, the shielding of the tuners on 6905 is worse, thus allowing interference.

[malakudi]

The performance of TBS6905 is unacceptable, we have 10 cards and all have the above mentioned issue. Interference when used side by side. We want to replace them with different card (TBS6904? don't know which is more similar to 100% working TBS6985), we send email to support but noone replies. Please reply ASAP.