A method performed by a master node, for handling connections to slave devices (121, 122, 123), which connections are Bluetooth connections, and which master node and slave devices (121, 122, 123) operates in a Bluetooth communication system, the method comprising: allocating to a first group, a first set of channels, and to a second group a second set of channels, which first set of channels relates to a first part of a frequency band supported by the master node, and which second set of channels relates to a second part of the frequency band that is different from the first part of the frequency band, assigning to the first group, a first connection between the master node and a first slave device, to use channels comprised in the first set of channels, and attenuating, using a first filter, for the connection in the first group, signals relating to any other group being allocated a set of channels, including the second group; and assigning to the second group, a second connection between the master node and a second slave device, to use channels comprised in the second set of channels, and attenuating, using a second filter, for the second connection in the second group, signals relating to any other group being allocated a set of channels, including the first group, wherein the master node comprises multiple antennas (171, 172), whereof each antenna is assigned to handle connections to one respective group out of any of the first group, and the second group, and wherein each antenna out of the multiple antennas, is connected to one filter out of: the first filter, and the second filter respectively; or wherein the master node comprises a single antenna comprising: a diplexer, wherein the diplexer comprises the first filter and the second filter. allocating to a first group, a first set of channels, and to a second group a second set of channels, which first set of channels relates to a first part of a frequency band supported by the master node, and which second set of channels relates to a second part of the frequency band that is different from the first part of the frequency band, assigning to the first group, a first connection between the master node and a first slave device, to use channels comprised in the first set of channels, and attenuating, using a first filter, for the connection in the first group, signals relating to any other group being allocated a set of channels, including the second group; and assigning to the second group, a second connection between the master node and a second slave device, to use channels comprised in the second set of channels, and attenuating, using a second filter, for the second connection in the second group, signals relating to any other group being allocated a set of channels, including the first group, wherein the master node comprises multiple antennas (171, 172), whereof each antenna is assigned to handle connections to one respective group out of any of the first group, and the second group, and wherein each antenna out of the multiple antennas, is connected to one filter out of: the first filter, and the second filter respectively; or wherein the master node comprises a single antenna comprising: a diplexer, wherein the diplexer comprises the first filter and the second filter.