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Hello! We have problems with DTMF tones on Snom D715, D765 and D725 phones on a 3CX PBX. At irregular intervals, the Snom phones stop sending DTMF tones. After a restart, the problem is gone for a short time. But comes back at irregular intervals. With firmware 8.9.3.66 the issue was “huge”. It seems to be fixed in firmware 8.9.3.87. Now, a new firmware is out: 8.9.3.88 and we have similar issues again. DTMF works but it is delayed. If I press a button, the DTMF signal is delayed for about 10 to 15 seconds. If I press DTMF keys several times in succession, you will not hear anything at first (no sound will be sent). Then suddenly all sounds are sent at once. Sometimes it works still fine. Sometimes with delay. We also unse the Snom DECT M700 system. DTMF here works perfect.