Hello all, I have run into some problems while building and running osmo-nitb, osmo-bts-trx and osmo-trx on Ubuntu 16.04. I am trying to create a self-contained gsm network box. I have successfully built libosmocore, libosmo-abis, libosmo-netif, libosmo-sccp, openbsc, osmo-bts and osmo-trx all from git sources, and i am also using linux call router. All make checks pass corrently without issues. As for the SDR side, i am have the latest UHD, SoapySDR and SoapyUHD, and latest LimeSuite library for LimeSDR support. SMS send/receive works correctly without any issues. Calling, however, works neither with osmo-nitb as standalone, neither with osmo-nitb with -m parameter + LCR. when trying to call, the receiving phone rings, but when trying to answer it randomly either gets stuck and does not answer, drops the call instantly or actually takes the call (and the elapsed seconds counter starts counting), but all you can hear is random noises coming both from the calling and from receiving phones, while the calling phone still shows that the call has not been answered, as in still calling. this is the debug info from osmo-trx: <0000> rsl.c:606 (bts=0,trx=0,ts=2,ss=0) Tx CHAN ACT ACK <0011> lapd_core.c:920 Store content res. (dl=0xb668cec8) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=0, V(R)=1 (dl=0xb668cec8 state LAPD_STATE_MF_EST) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=0, V(R)=1 (dl=0xb668cec8 state LAPD_STATE_MF_EST) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=1, V(R)=2 (dl=0xb668cec8 state LAPD_STATE_MF_EST) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=1, V(R)=2 (dl=0xb668cec8 state LAPD_STATE_MF_EST) <0000> rsl.c:1639 CRCX does not specify a remote IP <0000> rsl.c:1646 CRCX does not specify a remote port <0000> rsl.c:1650 speech mode: 16 <0000> rsl.c:1656 payload type: 3 <0000> rsl.c:1636 connect_ip 16777343 <0000> rsl.c:1643 connect_port 12405 <0000> rsl.c:1650 speech mode: 0 <0000> rsl.c:1656 payload type: 3 <0009> pcu_sock.c:668 PCU socket not connected, dropping message <0011> lapd_core.c:1556 N(S) sequence error: N(S)=2, V(R)=3 (dl=0xb668cec8 state LAPD_STATE_MF_EST) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=2, V(R)=3 (dl=0xb668cec8 state LAPD_STATE_MF_EST) <0009> pcu_sock.c:668 PCU socket not connected, dropping message <0009> pcu_sock.c:668 PCU socket not connected, dropping message <0009> pcu_sock.c:668 PCU socket not connected, dropping message <0000> rsl.c:606 (bts=0,trx=0,ts=3,ss=0) Tx CHAN ACT ACK <000e> l1sap.c:96 RTP clock out of sync with lower layer: 2080 vs 160 (2291865->2291921) <0011> lapd_core.c:920 Store content res. (dl=0xb66a83dc) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=0, V(R)=1 (dl=0xb66a83dc state LAPD_STATE_MF_EST) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=0, V(R)=1 (dl=0xb66a83dc state LAPD_STATE_MF_EST) <0000> rsl.c:1639 CRCX does not specify a remote IP <0000> rsl.c:1646 CRCX does not specify a remote port <0000> rsl.c:1650 speech mode: 16 <0000> rsl.c:1656 payload type: 3 <0011> lapd_core.c:1556 N(S) sequence error: N(S)=1, V(R)=2 (dl=0xb66a83dc state LAPD_STATE_MF_EST) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=1, V(R)=2 (dl=0xb66a83dc state LAPD_STATE_MF_EST) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=2, V(R)=3 (dl=0xb66a83dc state LAPD_STATE_MF_EST) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594400 vs 160 (2292212->2292182) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=2, V(R)=3 (dl=0xb66a83dc state LAPD_STATE_MF_EST) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2292208->2292246) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2292246->2292212) <0000> rsl.c:1636 connect_ip 16777343 <0000> rsl.c:1643 connect_port 12917 <0000> rsl.c:1650 speech mode: 0 <0000> rsl.c:1656 payload type: 3 <0011> lapd_core.c:1556 N(S) sequence error: N(S)=3, V(R)=4 (dl=0xb66a83dc state LAPD_STATE_MF_EST) <0011> lapd_core.c:1556 N(S) sequence error: N(S)=3, V(R)=4 (dl=0xb66a83dc state LAPD_STATE_MF_EST) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 2080 vs 160 (2292814->2292870) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2293165->2293131) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2293178->2293221) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594400 vs 160 (2293221->2293191) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2293200->2293239) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2293239->2293204) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2293404->2293447) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594400 vs 160 (2293447->2293417) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2293417->2293455) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2293455->2293421) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2293443->2293486) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594400 vs 160 (2293486->2293456) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2293469->2293507) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2293507->2293473) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2293677->2293720) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594080 vs 160 (2293720->2293681) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2293789->2293832) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594080 vs 160 (2293832->2293794) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1760 vs 160 (2293967->2294014) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594400 vs 160 (2294014->2293984) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2293989->2294027) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2294027->2293993) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2294240->2294283) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594400 vs 160 (2294283->2294253) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2294257->2294296) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2294296->2294262) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2294262->2294305) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594080 vs 160 (2294305->2294266) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1760 vs 160 (2294283->2294331) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2294331->2294296) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 480 vs 160 (2294318->2294331) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2294335->2294374) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2294374->2294340) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2294409->2294452) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594080 vs 160 (2294452->2294413) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1760 vs 160 (2294929->2294976) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594400 vs 160 (2294976->2294946) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2294951->2294989) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2294989->2294955) <0000> rsl.c:689 (bts=0,trx=0,ts=2,ss=0) Sending Connection Failure: cause = 0x01 <0011> lapdm.c:1144 ((nil)) RLL Message 'REL_REQ' received without LAPDm context. (sapi 0) <0000> rsl.c:1433 (bts=0,trx=0,ts=2,ss=0) Sending RTP delete indication: cause = Normal event, unspecified <0000> rsl.c:580 (bts=0,trx=0,ts=2,ss=0) Tx RF CHAN REL ACK <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2295705->2295748) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2295752->2295718) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2295817->2295860) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2295869->2295835) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2295960->2296003) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594400 vs 160 (2296003->2295973) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1440 vs 160 (2295978->2296016) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2296016->2295982) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 1600 vs 160 (2296030->2296073) <000e> l1sap.c:96 RTP clock out of sync with lower layer: 82594240 vs 160 (2296077->2296043) <0000> rsl.c:689 (bts=0,trx=0,ts=3,ss=0) Sending Connection Failure: cause = 0x01 <0011> lapdm.c:1144 ((nil)) RLL Message 'REL_REQ' received without LAPDm context. (sapi 0) <0000> rsl.c:1433 (bts=0,trx=0,ts=3,ss=0) Sending RTP delete indication: cause = Normal event, unspecified <0000> rsl.c:580 (bts=0,trx=0,ts=3,ss=0) Tx RF CHAN REL ACK osmo-nitb -c config.cfg -C -m -P <0004> abis_rsl.c:1852 BTS 0 CHAN RQD: reason: call re-establishment (ra=0x4f, neci=0x01, chreq_reason=0x02) <000a> bsc_api.c:415 Sending (bts=0,trx=0,ts=2,ss=0) ChanModify for speech: SPEECH_V1 on channel TCH_F <0004> abis_rsl.c:1852 BTS 0 CHAN RQD: reason: answer to paging (ra=0x27, neci=0x01, chreq_reason=0x01) <000a> bsc_api.c:415 Sending (bts=0,trx=0,ts=3,ss=0) ChanModify for speech: SPEECH_V1 on channel TCH_F <0004> abis_rsl.c:1358 (bts=0,trx=0,ts=2,ss=0) CONNECTION FAIL: RELEASING state ACTIVE CAUSE=0x01(Radio Link Failure) <0004> abis_rsl.c:1358 (bts=0,trx=0,ts=3,ss=0) CONNECTION FAIL: RELEASING state ACTIVE CAUSE=0x01(Radio Link Failure) versions of software: osmo-nitb --version OpenBSC version 1.0.0.14-98a2ba ~/Desktop/osmo/openbsc$ git log -1 commit 98a2ba4c57e95d2ce1e1e8147ea5a8d51788a191 Author: Vadim Yanitskiy &lt;axilirator(a)gmail.com&gt; Date:   Wed Jan 10 22:25:17 2018 +0600 ((*))   |  / \ OsmoBTS OsmoBTS version 0.7.0.77-54be ~/Desktop/osmo/osmo-bts$ git log -1 commit 54be46949e93e07e9e57b706388ebb832e5fad0a Author: Pau Espin Pedrol &lt;pespin(a)sysmocom.de&gt; Date:   Fri Feb 9 12:08:38 2018 +0100 osmo trx: ~/Desktop/osmo/osmo-trx$ git log -1 commit 77ce99ac6720896f504a0581a5c57b2929a13cef Author: Pau Espin Pedrol &lt;pespin(a)sysmocom.de&gt; Date:   Mon Feb 5 13:05:06 2018 +0100 older osmo-bts-trx does actually work at least somewhat, but then voice transmission stops after 10-20 seconds, or sometimes even after 4 minutes of talking, while . The older version is: commit 9982b95069c58a3cb9b97bb6bc75932db81886ad Author: Harald Welte &lt;laforge(a)gnumonks.org&gt; Date:   Tue Oct 24 18:42:30 2017 +0200 "OsmoBTS version 0.6.0.21-9982b-dirty" I would, however, like to use a newer, preferably the master branch version from git. Any help in dealing with this issue would be very greatly appreciated.