Problems with some Cisco 1850 Mobility Express APs

Hi there! On my Work Place we have 2x Cisco AP1852 (Mobility Express) and 3x Cisco CAP3602 as CAPWAPs connected to the virtual controller provided by the 1850s (so no dedicated appliance controller here)

Problem, when there are more people on the Office (about 70 distributed by all the APs), the clients connected to the 1850 loose conectivity multiple times per day :( The clients drop and then reconnects to the clossest AP, I can't find the reason... Halp!

Here are the Logs from when it happened just now:

Controller:

*spamApTask0: Aug 09 17:08:56.559: %LWAPP-3-REPLAY_ERR: spam_lrad.c:44908 The system has received replay error on slot 0, WLAN ID 1, count 2 from AP 20:3a:07:48:32:30

*apfMsConnTask_0: Aug 09 17:06:56.945: %APF-3-ASSOC_REQ_FAILED: apf_80211.c:9606 Ignoring 802.11 assoc request from mobile 60:36:dd:b9:6b:12 Since Dot11Radio 0 is not Enabled for AP:APPTL101 MAC:dc:ce:c1:23:3d:c0

*apfMsConnTask_0: Aug 09 17:06:56.934: %APF-3-ASSOC_REQ_FAILED: apf_80211.c:9606 Ignoring 802.11 assoc request from mobile e4:a7:a0:7d:a0:9b Since Dot11Radio 1 is not Enabled for AP:APPTL102 MAC:dc:ce:c1:23:48:a0

AP:

Aug 9 17:06:56 kernel: [*08/09/2018 16:06:56.5066] DOT11_DRV[0]: Stop Radio0

Aug 9 17:06:56 kernel: [*08/09/2018 16:06:56.5966] DOT11_DRV[1]: Stop Radio1

Aug 9 17:06:56 kernel: [*08/09/2018 16:06:56.6866] DOT11_DRV[0]: Start Radio0

Aug 9 17:06:56 kernel: [*08/09/2018 16:06:56.8165] DOT11_DRV[1]: Start Radio1

Aug 9 17:06:56 kernel: [*08/09/2018 16:06:56.8565] ol_if_dfs_enable: called

Aug 9 17:06:56 kernel: [*08/09/2018 16:06:56.8565] ieee80211_dfs_cac_start CAC Still Valid. Skip CAC

Aug 9 17:06:56 kernel: [*08/09/2018 16:06:56.9065] ol_if_dfs_enable: called

Aug 9 17:06:57 kernel: [*08/09/2018 16:06:57.1564] ol_if_dfs_enable: called

Controller Version: 8.5.131.0

Regards, John